(0) Obligation:

Q restricted rewrite system:
The TRS R consists of the following rules:

zeroscons(0, n__zeros)
U11(tt) → tt
U21(tt) → tt
U31(tt) → tt
U41(tt, V2) → U42(isNatIList(activate(V2)))
U42(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
isNat(n__0) → tt
isNat(n__length(V1)) → U11(isNatList(activate(V1)))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
isNatIList(V) → U31(isNatList(activate(V)))
isNatIList(n__zeros) → tt
isNatIList(n__cons(V1, V2)) → U41(isNat(activate(V1)), activate(V2))
isNatList(n__nil) → tt
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
length(nil) → 0
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
zerosn__zeros
0n__0
length(X) → n__length(X)
s(X) → n__s(X)
cons(X1, X2) → n__cons(X1, X2)
niln__nil
activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X

Q is empty.

(1) QTRSRRRProof (EQUIVALENT transformation)

Used ordering:
Polynomial interpretation [POLO]:

POL(0) = 0   
POL(U11(x1)) = x1   
POL(U21(x1)) = x1   
POL(U31(x1)) = x1   
POL(U41(x1, x2)) = 2·x1 + 2·x2   
POL(U42(x1)) = x1   
POL(U51(x1, x2)) = 2·x1 + 2·x2   
POL(U52(x1)) = x1   
POL(U61(x1, x2, x3)) = x1 + 2·x2 + 2·x3   
POL(U62(x1, x2)) = 2·x1 + 2·x2   
POL(activate(x1)) = x1   
POL(cons(x1, x2)) = 2·x1 + 2·x2   
POL(isNat(x1)) = x1   
POL(isNatIList(x1)) = 2·x1   
POL(isNatList(x1)) = 2·x1   
POL(length(x1)) = 2·x1   
POL(n__0) = 0   
POL(n__cons(x1, x2)) = 2·x1 + 2·x2   
POL(n__length(x1)) = 2·x1   
POL(n__nil) = 1   
POL(n__s(x1)) = x1   
POL(n__zeros) = 0   
POL(nil) = 1   
POL(s(x1)) = x1   
POL(tt) = 0   
POL(zeros) = 0   
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:

isNatList(n__nil) → tt
length(nil) → 0


(2) Obligation:

Q restricted rewrite system:
The TRS R consists of the following rules:

zeroscons(0, n__zeros)
U11(tt) → tt
U21(tt) → tt
U31(tt) → tt
U41(tt, V2) → U42(isNatIList(activate(V2)))
U42(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
isNat(n__0) → tt
isNat(n__length(V1)) → U11(isNatList(activate(V1)))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
isNatIList(V) → U31(isNatList(activate(V)))
isNatIList(n__zeros) → tt
isNatIList(n__cons(V1, V2)) → U41(isNat(activate(V1)), activate(V2))
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
zerosn__zeros
0n__0
length(X) → n__length(X)
s(X) → n__s(X)
cons(X1, X2) → n__cons(X1, X2)
niln__nil
activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X

Q is empty.

(3) QTRSRRRProof (EQUIVALENT transformation)

Used ordering:
Polynomial interpretation [POLO]:

POL(0) = 0   
POL(U11(x1)) = 1 + x1   
POL(U21(x1)) = x1   
POL(U31(x1)) = x1   
POL(U41(x1, x2)) = 2·x1 + 2·x2   
POL(U42(x1)) = x1   
POL(U51(x1, x2)) = 2·x1 + 2·x2   
POL(U52(x1)) = x1   
POL(U61(x1, x2, x3)) = 1 + x1 + 2·x2 + 2·x3   
POL(U62(x1, x2)) = 1 + x1 + 2·x2   
POL(activate(x1)) = x1   
POL(cons(x1, x2)) = 2·x1 + 2·x2   
POL(isNat(x1)) = 2·x1   
POL(isNatIList(x1)) = 2·x1   
POL(isNatList(x1)) = 2·x1   
POL(length(x1)) = 1 + 2·x1   
POL(n__0) = 0   
POL(n__cons(x1, x2)) = 2·x1 + 2·x2   
POL(n__length(x1)) = 1 + 2·x1   
POL(n__nil) = 0   
POL(n__s(x1)) = x1   
POL(n__zeros) = 0   
POL(nil) = 0   
POL(s(x1)) = x1   
POL(tt) = 0   
POL(zeros) = 0   
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:

U11(tt) → tt
isNat(n__length(V1)) → U11(isNatList(activate(V1)))


(4) Obligation:

Q restricted rewrite system:
The TRS R consists of the following rules:

zeroscons(0, n__zeros)
U21(tt) → tt
U31(tt) → tt
U41(tt, V2) → U42(isNatIList(activate(V2)))
U42(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
isNatIList(V) → U31(isNatList(activate(V)))
isNatIList(n__zeros) → tt
isNatIList(n__cons(V1, V2)) → U41(isNat(activate(V1)), activate(V2))
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
zerosn__zeros
0n__0
length(X) → n__length(X)
s(X) → n__s(X)
cons(X1, X2) → n__cons(X1, X2)
niln__nil
activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X

Q is empty.

(5) QTRSRRRProof (EQUIVALENT transformation)

Used ordering:
Polynomial interpretation [POLO]:

POL(0) = 0   
POL(U21(x1)) = x1   
POL(U31(x1)) = x1   
POL(U41(x1, x2)) = 1 + 2·x1 + 2·x2   
POL(U42(x1)) = x1   
POL(U51(x1, x2)) = x1 + 2·x2   
POL(U52(x1)) = x1   
POL(U61(x1, x2, x3)) = x1 + 2·x2 + x3   
POL(U62(x1, x2)) = x1 + 2·x2   
POL(activate(x1)) = x1   
POL(cons(x1, x2)) = 2·x1 + 2·x2   
POL(isNat(x1)) = x1   
POL(isNatIList(x1)) = 1 + 2·x1   
POL(isNatList(x1)) = 2·x1   
POL(length(x1)) = 2·x1   
POL(n__0) = 0   
POL(n__cons(x1, x2)) = 2·x1 + 2·x2   
POL(n__length(x1)) = 2·x1   
POL(n__nil) = 0   
POL(n__s(x1)) = x1   
POL(n__zeros) = 0   
POL(nil) = 0   
POL(s(x1)) = x1   
POL(tt) = 0   
POL(zeros) = 0   
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:

isNatIList(V) → U31(isNatList(activate(V)))
isNatIList(n__zeros) → tt


(6) Obligation:

Q restricted rewrite system:
The TRS R consists of the following rules:

zeroscons(0, n__zeros)
U21(tt) → tt
U31(tt) → tt
U41(tt, V2) → U42(isNatIList(activate(V2)))
U42(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
isNatIList(n__cons(V1, V2)) → U41(isNat(activate(V1)), activate(V2))
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
zerosn__zeros
0n__0
length(X) → n__length(X)
s(X) → n__s(X)
cons(X1, X2) → n__cons(X1, X2)
niln__nil
activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X

Q is empty.

(7) QTRSRRRProof (EQUIVALENT transformation)

Used ordering:
Polynomial interpretation [POLO]:

POL(0) = 0   
POL(U21(x1)) = x1   
POL(U31(x1)) = 1 + 2·x1   
POL(U41(x1, x2)) = 2·x1 + 2·x2   
POL(U42(x1)) = 2·x1   
POL(U51(x1, x2)) = x1 + 2·x2   
POL(U52(x1)) = x1   
POL(U61(x1, x2, x3)) = 2·x1 + 2·x2 + 2·x3   
POL(U62(x1, x2)) = 2·x1 + 2·x2   
POL(activate(x1)) = x1   
POL(cons(x1, x2)) = 2·x1 + 2·x2   
POL(isNat(x1)) = x1   
POL(isNatIList(x1)) = x1   
POL(isNatList(x1)) = x1   
POL(length(x1)) = 2·x1   
POL(n__0) = 0   
POL(n__cons(x1, x2)) = 2·x1 + 2·x2   
POL(n__length(x1)) = 2·x1   
POL(n__nil) = 0   
POL(n__s(x1)) = x1   
POL(n__zeros) = 0   
POL(nil) = 0   
POL(s(x1)) = x1   
POL(tt) = 0   
POL(zeros) = 0   
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:

U31(tt) → tt


(8) Obligation:

Q restricted rewrite system:
The TRS R consists of the following rules:

zeroscons(0, n__zeros)
U21(tt) → tt
U41(tt, V2) → U42(isNatIList(activate(V2)))
U42(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
isNatIList(n__cons(V1, V2)) → U41(isNat(activate(V1)), activate(V2))
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
zerosn__zeros
0n__0
length(X) → n__length(X)
s(X) → n__s(X)
cons(X1, X2) → n__cons(X1, X2)
niln__nil
activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X

Q is empty.

(9) DependencyPairsProof (EQUIVALENT transformation)

Using Dependency Pairs [AG00,LPAR04] we result in the following initial DP problem.

(10) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ZEROSCONS(0, n__zeros)
ZEROS01
U411(tt, V2) → U421(isNatIList(activate(V2)))
U411(tt, V2) → ISNATILIST(activate(V2))
U411(tt, V2) → ACTIVATE(V2)
U511(tt, V2) → U521(isNatList(activate(V2)))
U511(tt, V2) → ISNATLIST(activate(V2))
U511(tt, V2) → ACTIVATE(V2)
U611(tt, L, N) → U621(isNat(activate(N)), activate(L))
U611(tt, L, N) → ISNAT(activate(N))
U611(tt, L, N) → ACTIVATE(N)
U611(tt, L, N) → ACTIVATE(L)
U621(tt, L) → S(length(activate(L)))
U621(tt, L) → LENGTH(activate(L))
U621(tt, L) → ACTIVATE(L)
ISNAT(n__s(V1)) → U211(isNat(activate(V1)))
ISNAT(n__s(V1)) → ISNAT(activate(V1))
ISNAT(n__s(V1)) → ACTIVATE(V1)
ISNATILIST(n__cons(V1, V2)) → U411(isNat(activate(V1)), activate(V2))
ISNATILIST(n__cons(V1, V2)) → ISNAT(activate(V1))
ISNATILIST(n__cons(V1, V2)) → ACTIVATE(V1)
ISNATILIST(n__cons(V1, V2)) → ACTIVATE(V2)
ISNATLIST(n__cons(V1, V2)) → U511(isNat(activate(V1)), activate(V2))
ISNATLIST(n__cons(V1, V2)) → ISNAT(activate(V1))
ISNATLIST(n__cons(V1, V2)) → ACTIVATE(V1)
ISNATLIST(n__cons(V1, V2)) → ACTIVATE(V2)
LENGTH(cons(N, L)) → U611(isNatList(activate(L)), activate(L), N)
LENGTH(cons(N, L)) → ISNATLIST(activate(L))
LENGTH(cons(N, L)) → ACTIVATE(L)
ACTIVATE(n__zeros) → ZEROS
ACTIVATE(n__0) → 01
ACTIVATE(n__length(X)) → LENGTH(X)
ACTIVATE(n__s(X)) → S(X)
ACTIVATE(n__cons(X1, X2)) → CONS(X1, X2)
ACTIVATE(n__nil) → NIL

The TRS R consists of the following rules:

zeroscons(0, n__zeros)
U21(tt) → tt
U41(tt, V2) → U42(isNatIList(activate(V2)))
U42(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
isNatIList(n__cons(V1, V2)) → U41(isNat(activate(V1)), activate(V2))
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
zerosn__zeros
0n__0
length(X) → n__length(X)
s(X) → n__s(X)
cons(X1, X2) → n__cons(X1, X2)
niln__nil
activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(11) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 2 SCCs with 15 less nodes.

(12) Complex Obligation (AND)

(13) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ACTIVATE(n__length(X)) → LENGTH(X)
LENGTH(cons(N, L)) → U611(isNatList(activate(L)), activate(L), N)
U611(tt, L, N) → U621(isNat(activate(N)), activate(L))
U621(tt, L) → LENGTH(activate(L))
LENGTH(cons(N, L)) → ISNATLIST(activate(L))
ISNATLIST(n__cons(V1, V2)) → U511(isNat(activate(V1)), activate(V2))
U511(tt, V2) → ISNATLIST(activate(V2))
ISNATLIST(n__cons(V1, V2)) → ISNAT(activate(V1))
ISNAT(n__s(V1)) → ISNAT(activate(V1))
ISNAT(n__s(V1)) → ACTIVATE(V1)
ISNATLIST(n__cons(V1, V2)) → ACTIVATE(V1)
ISNATLIST(n__cons(V1, V2)) → ACTIVATE(V2)
U511(tt, V2) → ACTIVATE(V2)
LENGTH(cons(N, L)) → ACTIVATE(L)
U621(tt, L) → ACTIVATE(L)
U611(tt, L, N) → ISNAT(activate(N))
U611(tt, L, N) → ACTIVATE(N)
U611(tt, L, N) → ACTIVATE(L)

The TRS R consists of the following rules:

zeroscons(0, n__zeros)
U21(tt) → tt
U41(tt, V2) → U42(isNatIList(activate(V2)))
U42(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
isNatIList(n__cons(V1, V2)) → U41(isNat(activate(V1)), activate(V2))
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
zerosn__zeros
0n__0
length(X) → n__length(X)
s(X) → n__s(X)
cons(X1, X2) → n__cons(X1, X2)
niln__nil
activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(14) UsableRulesReductionPairsProof (EQUIVALENT transformation)

By using the usable rules with reduction pair processor [LPAR04] with a polynomial ordering [POLO], all dependency pairs and the corresponding usable rules [FROCOS05] can be oriented non-strictly. All non-usable rules are removed, and those dependency pairs and usable rules that have been oriented strictly or contain non-usable symbols in their left-hand side are removed as well.

The following dependency pairs can be deleted:

ACTIVATE(n__length(X)) → LENGTH(X)
The following rules are removed from R:

U41(tt, V2) → U42(isNatIList(activate(V2)))
U42(tt) → tt
isNatIList(n__cons(V1, V2)) → U41(isNat(activate(V1)), activate(V2))
Used ordering: POLO with Polynomial interpretation [POLO]:

POL(0) = 0   
POL(ACTIVATE(x1)) = 2·x1   
POL(ISNAT(x1)) = 2·x1   
POL(ISNATLIST(x1)) = 2·x1   
POL(LENGTH(x1)) = 2·x1   
POL(U21(x1)) = x1   
POL(U51(x1, x2)) = x1 + 2·x2   
POL(U511(x1, x2)) = 2·x1 + 2·x2   
POL(U52(x1)) = 2·x1   
POL(U61(x1, x2, x3)) = 2 + 2·x1 + 2·x2 + 2·x3   
POL(U611(x1, x2, x3)) = x1 + 2·x2 + 2·x3   
POL(U62(x1, x2)) = 2 + x1 + 2·x2   
POL(U621(x1, x2)) = x1 + 2·x2   
POL(activate(x1)) = x1   
POL(cons(x1, x2)) = 2·x1 + 2·x2   
POL(isNat(x1)) = 2·x1   
POL(isNatList(x1)) = x1   
POL(length(x1)) = 2 + 2·x1   
POL(n__0) = 0   
POL(n__cons(x1, x2)) = 2·x1 + 2·x2   
POL(n__length(x1)) = 2 + 2·x1   
POL(n__nil) = 0   
POL(n__s(x1)) = x1   
POL(n__zeros) = 0   
POL(nil) = 0   
POL(s(x1)) = x1   
POL(tt) = 0   
POL(zeros) = 0   

(15) Obligation:

Q DP problem:
The TRS P consists of the following rules:

LENGTH(cons(N, L)) → U611(isNatList(activate(L)), activate(L), N)
U611(tt, L, N) → U621(isNat(activate(N)), activate(L))
U621(tt, L) → LENGTH(activate(L))
LENGTH(cons(N, L)) → ISNATLIST(activate(L))
ISNATLIST(n__cons(V1, V2)) → U511(isNat(activate(V1)), activate(V2))
U511(tt, V2) → ISNATLIST(activate(V2))
ISNATLIST(n__cons(V1, V2)) → ISNAT(activate(V1))
ISNAT(n__s(V1)) → ISNAT(activate(V1))
ISNAT(n__s(V1)) → ACTIVATE(V1)
ISNATLIST(n__cons(V1, V2)) → ACTIVATE(V1)
ISNATLIST(n__cons(V1, V2)) → ACTIVATE(V2)
U511(tt, V2) → ACTIVATE(V2)
LENGTH(cons(N, L)) → ACTIVATE(L)
U621(tt, L) → ACTIVATE(L)
U611(tt, L, N) → ISNAT(activate(N))
U611(tt, L, N) → ACTIVATE(N)
U611(tt, L, N) → ACTIVATE(L)

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(16) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 3 SCCs with 11 less nodes.

(17) Complex Obligation (AND)

(18) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNAT(n__s(V1)) → ISNAT(activate(V1))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(19) QDPOrderProof (EQUIVALENT transformation)

We use the reduction pair processor [LPAR04,JAR06].


The following pairs can be oriented strictly and are deleted.


ISNAT(n__s(V1)) → ISNAT(activate(V1))
The remaining pairs can at least be oriented weakly.
Used ordering: Polynomial Order [NEGPOLO,POLO] with Interpretation:

POL( ISNAT(x1) ) = x1 + 2


POL( activate(x1) ) = x1


POL( n__zeros ) = 2


POL( zeros ) = 2


POL( n__0 ) = 2


POL( 0 ) = 2


POL( n__length(x1) ) = 0


POL( length(x1) ) = max{0, -2}


POL( n__s(x1) ) = 2x1 + 1


POL( s(x1) ) = 2x1 + 1


POL( n__cons(x1, x2) ) = 0


POL( cons(x1, x2) ) = max{0, -2}


POL( n__nil ) = 2


POL( nil ) = 2


POL( U61(x1, ..., x3) ) = max{0, 2x1 - 1}


POL( isNatList(x1) ) = max{0, -2}


POL( U51(x1, x2) ) = max{0, -2}


POL( isNat(x1) ) = max{0, x1 - 1}


POL( U21(x1) ) = max{0, 2x1 - 1}


POL( U62(x1, x2) ) = 1


POL( tt ) = 1


POL( U52(x1) ) = x1



The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
length(X) → n__length(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
s(X) → n__s(X)
zeroscons(0, n__zeros)
zerosn__zeros
0n__0
cons(X1, X2) → n__cons(X1, X2)
niln__nil

(20) Obligation:

Q DP problem:
P is empty.
The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(21) PisEmptyProof (EQUIVALENT transformation)

The TRS P is empty. Hence, there is no (P,Q,R) chain.

(22) YES

(23) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, V2) → ISNATLIST(activate(V2))
ISNATLIST(n__cons(V1, V2)) → U511(isNat(activate(V1)), activate(V2))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(24) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U511(tt, V2) → ISNATLIST(activate(V2)) at position [0] we obtained the following new rules [LPAR04]:

U511(tt, n__zeros) → ISNATLIST(zeros)
U511(tt, n__0) → ISNATLIST(0)
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
U511(tt, n__s(x0)) → ISNATLIST(s(x0))
U511(tt, n__cons(x0, x1)) → ISNATLIST(cons(x0, x1))
U511(tt, n__nil) → ISNATLIST(nil)
U511(tt, x0) → ISNATLIST(x0)

(25) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATLIST(n__cons(V1, V2)) → U511(isNat(activate(V1)), activate(V2))
U511(tt, n__zeros) → ISNATLIST(zeros)
U511(tt, n__0) → ISNATLIST(0)
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
U511(tt, n__s(x0)) → ISNATLIST(s(x0))
U511(tt, n__cons(x0, x1)) → ISNATLIST(cons(x0, x1))
U511(tt, n__nil) → ISNATLIST(nil)
U511(tt, x0) → ISNATLIST(x0)

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(26) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATLIST(n__cons(V1, V2)) → U511(isNat(activate(V1)), activate(V2)) at position [0] we obtained the following new rules [LPAR04]:

ISNATLIST(n__cons(n__zeros, y1)) → U511(isNat(zeros), activate(y1))
ISNATLIST(n__cons(n__0, y1)) → U511(isNat(0), activate(y1))
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(s(x0)), activate(y1))
ISNATLIST(n__cons(n__cons(x0, x1), y1)) → U511(isNat(cons(x0, x1)), activate(y1))
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))

(27) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, n__zeros) → ISNATLIST(zeros)
U511(tt, n__0) → ISNATLIST(0)
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
U511(tt, n__s(x0)) → ISNATLIST(s(x0))
U511(tt, n__cons(x0, x1)) → ISNATLIST(cons(x0, x1))
U511(tt, n__nil) → ISNATLIST(nil)
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(n__zeros, y1)) → U511(isNat(zeros), activate(y1))
ISNATLIST(n__cons(n__0, y1)) → U511(isNat(0), activate(y1))
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(s(x0)), activate(y1))
ISNATLIST(n__cons(n__cons(x0, x1), y1)) → U511(isNat(cons(x0, x1)), activate(y1))
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(28) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U511(tt, n__zeros) → ISNATLIST(zeros) at position [0] we obtained the following new rules [LPAR04]:

U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
U511(tt, n__zeros) → ISNATLIST(n__zeros)

(29) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, n__0) → ISNATLIST(0)
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
U511(tt, n__s(x0)) → ISNATLIST(s(x0))
U511(tt, n__cons(x0, x1)) → ISNATLIST(cons(x0, x1))
U511(tt, n__nil) → ISNATLIST(nil)
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(n__zeros, y1)) → U511(isNat(zeros), activate(y1))
ISNATLIST(n__cons(n__0, y1)) → U511(isNat(0), activate(y1))
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(s(x0)), activate(y1))
ISNATLIST(n__cons(n__cons(x0, x1), y1)) → U511(isNat(cons(x0, x1)), activate(y1))
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
U511(tt, n__zeros) → ISNATLIST(n__zeros)

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(30) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(31) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATLIST(n__cons(n__zeros, y1)) → U511(isNat(zeros), activate(y1))
U511(tt, n__0) → ISNATLIST(0)
ISNATLIST(n__cons(n__0, y1)) → U511(isNat(0), activate(y1))
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__s(x0)) → ISNATLIST(s(x0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(s(x0)), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(cons(x0, x1))
ISNATLIST(n__cons(n__cons(x0, x1), y1)) → U511(isNat(cons(x0, x1)), activate(y1))
U511(tt, n__nil) → ISNATLIST(nil)
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(32) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATLIST(n__cons(n__zeros, y1)) → U511(isNat(zeros), activate(y1)) at position [0] we obtained the following new rules [LPAR04]:

ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(n__zeros), activate(y0))

(33) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, n__0) → ISNATLIST(0)
ISNATLIST(n__cons(n__0, y1)) → U511(isNat(0), activate(y1))
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__s(x0)) → ISNATLIST(s(x0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(s(x0)), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(cons(x0, x1))
ISNATLIST(n__cons(n__cons(x0, x1), y1)) → U511(isNat(cons(x0, x1)), activate(y1))
U511(tt, n__nil) → ISNATLIST(nil)
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(n__zeros), activate(y0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(34) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(35) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATLIST(n__cons(n__0, y1)) → U511(isNat(0), activate(y1))
U511(tt, n__0) → ISNATLIST(0)
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(s(x0)), activate(y1))
U511(tt, n__s(x0)) → ISNATLIST(s(x0))
ISNATLIST(n__cons(n__cons(x0, x1), y1)) → U511(isNat(cons(x0, x1)), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(cons(x0, x1))
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
U511(tt, n__nil) → ISNATLIST(nil)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(36) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATLIST(n__cons(n__0, y1)) → U511(isNat(0), activate(y1)) at position [0] we obtained the following new rules [LPAR04]:

ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))

(37) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, n__0) → ISNATLIST(0)
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(s(x0)), activate(y1))
U511(tt, n__s(x0)) → ISNATLIST(s(x0))
ISNATLIST(n__cons(n__cons(x0, x1), y1)) → U511(isNat(cons(x0, x1)), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(cons(x0, x1))
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
U511(tt, n__nil) → ISNATLIST(nil)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(38) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U511(tt, n__0) → ISNATLIST(0) at position [0] we obtained the following new rules [LPAR04]:

U511(tt, n__0) → ISNATLIST(n__0)

(39) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(s(x0)), activate(y1))
U511(tt, n__s(x0)) → ISNATLIST(s(x0))
ISNATLIST(n__cons(n__cons(x0, x1), y1)) → U511(isNat(cons(x0, x1)), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(cons(x0, x1))
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
U511(tt, n__nil) → ISNATLIST(nil)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
U511(tt, n__0) → ISNATLIST(n__0)

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(40) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(41) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__s(x0)) → ISNATLIST(s(x0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(s(x0)), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(cons(x0, x1))
ISNATLIST(n__cons(n__cons(x0, x1), y1)) → U511(isNat(cons(x0, x1)), activate(y1))
U511(tt, n__nil) → ISNATLIST(nil)
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(42) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U511(tt, n__s(x0)) → ISNATLIST(s(x0)) at position [0] we obtained the following new rules [LPAR04]:

U511(tt, n__s(x0)) → ISNATLIST(n__s(x0))

(43) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(s(x0)), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(cons(x0, x1))
ISNATLIST(n__cons(n__cons(x0, x1), y1)) → U511(isNat(cons(x0, x1)), activate(y1))
U511(tt, n__nil) → ISNATLIST(nil)
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
U511(tt, n__s(x0)) → ISNATLIST(n__s(x0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(44) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(45) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(s(x0)), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(cons(x0, x1))
ISNATLIST(n__cons(n__cons(x0, x1), y1)) → U511(isNat(cons(x0, x1)), activate(y1))
U511(tt, n__nil) → ISNATLIST(nil)
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(46) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(s(x0)), activate(y1)) at position [0] we obtained the following new rules [LPAR04]:

ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))

(47) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
U511(tt, n__cons(x0, x1)) → ISNATLIST(cons(x0, x1))
ISNATLIST(n__cons(n__cons(x0, x1), y1)) → U511(isNat(cons(x0, x1)), activate(y1))
U511(tt, n__nil) → ISNATLIST(nil)
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(48) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U511(tt, n__cons(x0, x1)) → ISNATLIST(cons(x0, x1)) at position [0] we obtained the following new rules [LPAR04]:

U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))

(49) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__cons(x0, x1), y1)) → U511(isNat(cons(x0, x1)), activate(y1))
U511(tt, n__nil) → ISNATLIST(nil)
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(50) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATLIST(n__cons(n__cons(x0, x1), y1)) → U511(isNat(cons(x0, x1)), activate(y1)) at position [0] we obtained the following new rules [LPAR04]:

ISNATLIST(n__cons(n__cons(x0, x1), y2)) → U511(isNat(n__cons(x0, x1)), activate(y2))

(51) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
U511(tt, n__nil) → ISNATLIST(nil)
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__cons(x0, x1), y2)) → U511(isNat(n__cons(x0, x1)), activate(y2))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(52) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(53) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__nil) → ISNATLIST(nil)
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(54) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U511(tt, n__nil) → ISNATLIST(nil) at position [0] we obtained the following new rules [LPAR04]:

U511(tt, n__nil) → ISNATLIST(n__nil)

(55) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))
U511(tt, n__nil) → ISNATLIST(n__nil)

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(56) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(57) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(58) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATLIST(n__cons(n__nil, y1)) → U511(isNat(nil), activate(y1)) at position [0] we obtained the following new rules [LPAR04]:

ISNATLIST(n__cons(n__nil, y0)) → U511(isNat(n__nil), activate(y0))

(59) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))
ISNATLIST(n__cons(n__nil, y0)) → U511(isNat(n__nil), activate(y0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(60) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(61) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(62) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U511(tt, n__zeros) → ISNATLIST(cons(0, n__zeros)) at position [0] we obtained the following new rules [LPAR04]:

U511(tt, n__zeros) → ISNATLIST(n__cons(0, n__zeros))
U511(tt, n__zeros) → ISNATLIST(cons(n__0, n__zeros))

(63) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))
U511(tt, n__zeros) → ISNATLIST(n__cons(0, n__zeros))
U511(tt, n__zeros) → ISNATLIST(cons(n__0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(64) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(0, n__zeros)), activate(y0)) at position [0] we obtained the following new rules [LPAR04]:

ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(n__cons(0, n__zeros)), activate(y0))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(n__0, n__zeros)), activate(y0))

(65) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))
U511(tt, n__zeros) → ISNATLIST(n__cons(0, n__zeros))
U511(tt, n__zeros) → ISNATLIST(cons(n__0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(n__cons(0, n__zeros)), activate(y0))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(n__0, n__zeros)), activate(y0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(66) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(67) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))
U511(tt, n__zeros) → ISNATLIST(n__cons(0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(n__0, n__zeros)), activate(y0))
U511(tt, n__zeros) → ISNATLIST(cons(n__0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(68) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(cons(n__0, n__zeros)), activate(y0)) at position [0] we obtained the following new rules [LPAR04]:

ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(n__cons(n__0, n__zeros)), activate(y0))

(69) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))
U511(tt, n__zeros) → ISNATLIST(n__cons(0, n__zeros))
U511(tt, n__zeros) → ISNATLIST(cons(n__0, n__zeros))
ISNATLIST(n__cons(n__zeros, y0)) → U511(isNat(n__cons(n__0, n__zeros)), activate(y0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(70) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(71) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
U511(tt, n__zeros) → ISNATLIST(n__cons(0, n__zeros))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))
U511(tt, n__zeros) → ISNATLIST(cons(n__0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(72) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U511(tt, n__zeros) → ISNATLIST(cons(n__0, n__zeros)) at position [0] we obtained the following new rules [LPAR04]:

U511(tt, n__zeros) → ISNATLIST(n__cons(n__0, n__zeros))

(73) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, n__length(x0)) → ISNATLIST(length(x0))
ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
U511(tt, n__zeros) → ISNATLIST(n__cons(0, n__zeros))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))
U511(tt, n__zeros) → ISNATLIST(n__cons(n__0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(74) MRRProof (EQUIVALENT transformation)

By using the rule removal processor [LPAR04] with the following ordering, at least one Dependency Pair or term rewrite system rule of this QDP problem can be strictly oriented.
Strictly oriented dependency pairs:

ISNATLIST(n__cons(n__length(x0), y1)) → U511(isNat(length(x0)), activate(y1))


Used ordering: Polynomial interpretation [POLO]:

POL(0) = 0   
POL(ISNATLIST(x1)) = 2·x1   
POL(U21(x1)) = x1   
POL(U51(x1, x2)) = 2·x1 + 2·x2   
POL(U511(x1, x2)) = 2·x1 + 2·x2   
POL(U52(x1)) = 2·x1   
POL(U61(x1, x2, x3)) = 2 + x1 + 2·x2 + 2·x3   
POL(U62(x1, x2)) = 2 + x1 + 2·x2   
POL(activate(x1)) = x1   
POL(cons(x1, x2)) = 2·x1 + 2·x2   
POL(isNat(x1)) = x1   
POL(isNatList(x1)) = x1   
POL(length(x1)) = 2 + 2·x1   
POL(n__0) = 0   
POL(n__cons(x1, x2)) = 2·x1 + 2·x2   
POL(n__length(x1)) = 2 + 2·x1   
POL(n__nil) = 0   
POL(n__s(x1)) = x1   
POL(n__zeros) = 0   
POL(nil) = 0   
POL(s(x1)) = x1   
POL(tt) = 0   
POL(zeros) = 0   

(75) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, n__length(x0)) → ISNATLIST(length(x0))
U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
U511(tt, n__zeros) → ISNATLIST(n__cons(0, n__zeros))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))
U511(tt, n__zeros) → ISNATLIST(n__cons(n__0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(76) MRRProof (EQUIVALENT transformation)

By using the rule removal processor [LPAR04] with the following ordering, at least one Dependency Pair or term rewrite system rule of this QDP problem can be strictly oriented.
Strictly oriented dependency pairs:

U511(tt, n__length(x0)) → ISNATLIST(length(x0))


Used ordering: Polynomial interpretation [POLO]:

POL(0) = 0   
POL(ISNATLIST(x1)) = x1   
POL(U21(x1)) = x1   
POL(U51(x1, x2)) = 2·x1 + 2·x2   
POL(U511(x1, x2)) = 2·x1 + 2·x2   
POL(U52(x1)) = 2·x1   
POL(U61(x1, x2, x3)) = 1 + 2·x1 + 2·x2 + 2·x3   
POL(U62(x1, x2)) = 1 + 2·x1 + 2·x2   
POL(activate(x1)) = x1   
POL(cons(x1, x2)) = 2·x1 + 2·x2   
POL(isNat(x1)) = x1   
POL(isNatList(x1)) = x1   
POL(length(x1)) = 1 + 2·x1   
POL(n__0) = 0   
POL(n__cons(x1, x2)) = 2·x1 + 2·x2   
POL(n__length(x1)) = 1 + 2·x1   
POL(n__nil) = 0   
POL(n__s(x1)) = x1   
POL(n__zeros) = 0   
POL(nil) = 0   
POL(s(x1)) = x1   
POL(tt) = 0   
POL(zeros) = 0   

(77) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
U511(tt, n__zeros) → ISNATLIST(n__cons(0, n__zeros))
ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))
U511(tt, n__zeros) → ISNATLIST(n__cons(n__0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(78) QDPOrderProof (EQUIVALENT transformation)

We use the reduction pair processor [LPAR04,JAR06].


The following pairs can be oriented strictly and are deleted.


ISNATLIST(n__cons(n__s(x0), y1)) → U511(isNat(n__s(x0)), activate(y1))
The remaining pairs can at least be oriented weakly.
Used ordering: Polynomial interpretation [POLO]:

POL(0) = 0   
POL(ISNATLIST(x1)) = x1   
POL(U21(x1)) = 0   
POL(U51(x1, x2)) = 1 + x2   
POL(U511(x1, x2)) = x2   
POL(U52(x1)) = 1   
POL(U61(x1, x2, x3)) = 1 + x2   
POL(U62(x1, x2)) = 1 + x2   
POL(activate(x1)) = x1   
POL(cons(x1, x2)) = x1 + x2   
POL(isNat(x1)) = 1   
POL(isNatList(x1)) = 1 + x1   
POL(length(x1)) = 1 + x1   
POL(n__0) = 0   
POL(n__cons(x1, x2)) = x1 + x2   
POL(n__length(x1)) = 1 + x1   
POL(n__nil) = 0   
POL(n__s(x1)) = 1   
POL(n__zeros) = 0   
POL(nil) = 0   
POL(s(x1)) = 1   
POL(tt) = 0   
POL(zeros) = 0   

The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:

isNat(n__s(V1)) → U21(isNat(activate(V1)))
activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
0n__0
length(X) → n__length(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
s(X) → n__s(X)
zeroscons(0, n__zeros)
zerosn__zeros
cons(X1, X2) → n__cons(X1, X2)
niln__nil

(79) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U511(tt, x0) → ISNATLIST(x0)
ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))
U511(tt, n__cons(x0, x1)) → ISNATLIST(n__cons(x0, x1))
ISNATLIST(n__cons(n__0, y0)) → U511(isNat(n__0), activate(y0))
U511(tt, n__zeros) → ISNATLIST(n__cons(0, n__zeros))
U511(tt, n__zeros) → ISNATLIST(n__cons(n__0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(80) NonTerminationLoopProof (EQUIVALENT transformation)

We used the non-termination processor [FROCOS05] to show that the DP problem is infinite.
Found a loop by narrowing to the left:

s = U511(isNat(n__0), activate(n__zeros)) evaluates to t =U511(isNat(n__0), activate(n__zeros))

Thus s starts an infinite chain as s semiunifies with t with the following substitutions:
  • Matcher: [ ]
  • Semiunifier: [ ]




Rewriting sequence

U511(isNat(n__0), activate(n__zeros))U511(isNat(n__0), n__zeros)
with rule activate(X) → X at position [1] and matcher [X / n__zeros]

U511(isNat(n__0), n__zeros)U511(tt, n__zeros)
with rule isNat(n__0) → tt at position [0] and matcher [ ]

U511(tt, n__zeros)ISNATLIST(n__cons(n__0, n__zeros))
with rule U511(tt, n__zeros) → ISNATLIST(n__cons(n__0, n__zeros)) at position [] and matcher [ ]

ISNATLIST(n__cons(n__0, n__zeros))U511(isNat(n__0), activate(n__zeros))
with rule ISNATLIST(n__cons(x0, y1)) → U511(isNat(x0), activate(y1))

Now applying the matcher to the start term leads to a term which is equal to the last term in the rewriting sequence


All these steps are and every following step will be a correct step w.r.t to Q.



(81) NO

(82) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U611(tt, L, N) → U621(isNat(activate(N)), activate(L))
U621(tt, L) → LENGTH(activate(L))
LENGTH(cons(N, L)) → U611(isNatList(activate(L)), activate(L), N)

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(83) QDPOrderProof (EQUIVALENT transformation)

We use the reduction pair processor [LPAR04,JAR06].


The following pairs can be oriented strictly and are deleted.


U621(tt, L) → LENGTH(activate(L))
LENGTH(cons(N, L)) → U611(isNatList(activate(L)), activate(L), N)
The remaining pairs can at least be oriented weakly.
Used ordering: Combined order from the following AFS and order.
U611(x1, x2, x3)  =  U611(x1)
tt  =  tt
U621(x1, x2)  =  U621(x1)
isNat(x1)  =  isNat
activate(x1)  =  activate(x1)
LENGTH(x1)  =  LENGTH
cons(x1, x2)  =  x2
isNatList(x1)  =  isNatList
n__zeros  =  n__zeros
zeros  =  zeros
n__0  =  n__0
0  =  0
n__length(x1)  =  n__length(x1)
length(x1)  =  length(x1)
n__s(x1)  =  n__s
s(x1)  =  s
n__cons(x1, x2)  =  x2
n__nil  =  n__nil
nil  =  nil
U21(x1)  =  x1
U51(x1, x2)  =  U51
U61(x1, x2, x3)  =  U61(x1, x2)
U52(x1)  =  x1
U62(x1, x2)  =  U62(x1)

Recursive path order with status [RPO].
Quasi-Precedence:
[nlength1, length1] > [activate1, U612, U621] > [tt, isNat, LENGTH, s] > [U61^11, U62^11]
[nlength1, length1] > [activate1, U612, U621] > [tt, isNat, LENGTH, s] > [isNatList, U51]
[nlength1, length1] > [activate1, U612, U621] > [tt, isNat, LENGTH, s] > ns
[nlength1, length1] > [activate1, U612, U621] > zeros > nzeros
[nlength1, length1] > [activate1, U612, U621] > 0 > n0
[nlength1, length1] > [activate1, U612, U621] > nil > nnil

Status:
U61^11: multiset
tt: multiset
U62^11: multiset
isNat: []
activate1: multiset
LENGTH: []
isNatList: multiset
nzeros: multiset
zeros: multiset
n0: multiset
0: multiset
nlength1: multiset
length1: multiset
ns: multiset
s: multiset
nnil: multiset
nil: multiset
U51: multiset
U612: multiset
U621: multiset


The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
length(X) → n__length(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
s(X) → n__s(X)
zeroscons(0, n__zeros)
zerosn__zeros
0n__0
cons(X1, X2) → n__cons(X1, X2)
niln__nil

(84) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U611(tt, L, N) → U621(isNat(activate(N)), activate(L))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U62(tt, L) → s(length(activate(L)))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(85) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 0 SCCs with 1 less node.

(86) TRUE

(87) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, V2) → ISNATILIST(activate(V2))
ISNATILIST(n__cons(V1, V2)) → U411(isNat(activate(V1)), activate(V2))

The TRS R consists of the following rules:

zeroscons(0, n__zeros)
U21(tt) → tt
U41(tt, V2) → U42(isNatIList(activate(V2)))
U42(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
isNatIList(n__cons(V1, V2)) → U41(isNat(activate(V1)), activate(V2))
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
zerosn__zeros
0n__0
length(X) → n__length(X)
s(X) → n__s(X)
cons(X1, X2) → n__cons(X1, X2)
niln__nil
activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(88) UsableRulesReductionPairsProof (EQUIVALENT transformation)

By using the usable rules with reduction pair processor [LPAR04] with a polynomial ordering [POLO], all dependency pairs and the corresponding usable rules [FROCOS05] can be oriented non-strictly. All non-usable rules are removed, and those dependency pairs and usable rules that have been oriented strictly or contain non-usable symbols in their left-hand side are removed as well.

No dependency pairs are removed.

The following rules are removed from R:

U41(tt, V2) → U42(isNatIList(activate(V2)))
U42(tt) → tt
isNatIList(n__cons(V1, V2)) → U41(isNat(activate(V1)), activate(V2))
Used ordering: POLO with Polynomial interpretation [POLO]:

POL(0) = 0   
POL(ISNATILIST(x1)) = x1   
POL(U21(x1)) = x1   
POL(U411(x1, x2)) = x1 + x2   
POL(U51(x1, x2)) = x1 + 2·x2   
POL(U52(x1)) = x1   
POL(U61(x1, x2, x3)) = x1 + 2·x2 + 2·x3   
POL(U62(x1, x2)) = x1 + 2·x2   
POL(activate(x1)) = x1   
POL(cons(x1, x2)) = x1 + 2·x2   
POL(isNat(x1)) = x1   
POL(isNatList(x1)) = x1   
POL(length(x1)) = 2·x1   
POL(n__0) = 0   
POL(n__cons(x1, x2)) = x1 + 2·x2   
POL(n__length(x1)) = 2·x1   
POL(n__nil) = 2   
POL(n__s(x1)) = x1   
POL(n__zeros) = 0   
POL(nil) = 2   
POL(s(x1)) = x1   
POL(tt) = 0   
POL(zeros) = 0   

(89) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, V2) → ISNATILIST(activate(V2))
ISNATILIST(n__cons(V1, V2)) → U411(isNat(activate(V1)), activate(V2))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(90) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U411(tt, V2) → ISNATILIST(activate(V2)) at position [0] we obtained the following new rules [LPAR04]:

U411(tt, n__zeros) → ISNATILIST(zeros)
U411(tt, n__0) → ISNATILIST(0)
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
U411(tt, n__s(x0)) → ISNATILIST(s(x0))
U411(tt, n__cons(x0, x1)) → ISNATILIST(cons(x0, x1))
U411(tt, n__nil) → ISNATILIST(nil)
U411(tt, x0) → ISNATILIST(x0)

(91) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATILIST(n__cons(V1, V2)) → U411(isNat(activate(V1)), activate(V2))
U411(tt, n__zeros) → ISNATILIST(zeros)
U411(tt, n__0) → ISNATILIST(0)
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
U411(tt, n__s(x0)) → ISNATILIST(s(x0))
U411(tt, n__cons(x0, x1)) → ISNATILIST(cons(x0, x1))
U411(tt, n__nil) → ISNATILIST(nil)
U411(tt, x0) → ISNATILIST(x0)

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(92) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATILIST(n__cons(V1, V2)) → U411(isNat(activate(V1)), activate(V2)) at position [0] we obtained the following new rules [LPAR04]:

ISNATILIST(n__cons(n__zeros, y1)) → U411(isNat(zeros), activate(y1))
ISNATILIST(n__cons(n__0, y1)) → U411(isNat(0), activate(y1))
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(s(x0)), activate(y1))
ISNATILIST(n__cons(n__cons(x0, x1), y1)) → U411(isNat(cons(x0, x1)), activate(y1))
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))

(93) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, n__zeros) → ISNATILIST(zeros)
U411(tt, n__0) → ISNATILIST(0)
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
U411(tt, n__s(x0)) → ISNATILIST(s(x0))
U411(tt, n__cons(x0, x1)) → ISNATILIST(cons(x0, x1))
U411(tt, n__nil) → ISNATILIST(nil)
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(n__zeros, y1)) → U411(isNat(zeros), activate(y1))
ISNATILIST(n__cons(n__0, y1)) → U411(isNat(0), activate(y1))
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(s(x0)), activate(y1))
ISNATILIST(n__cons(n__cons(x0, x1), y1)) → U411(isNat(cons(x0, x1)), activate(y1))
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(94) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U411(tt, n__zeros) → ISNATILIST(zeros) at position [0] we obtained the following new rules [LPAR04]:

U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
U411(tt, n__zeros) → ISNATILIST(n__zeros)

(95) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, n__0) → ISNATILIST(0)
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
U411(tt, n__s(x0)) → ISNATILIST(s(x0))
U411(tt, n__cons(x0, x1)) → ISNATILIST(cons(x0, x1))
U411(tt, n__nil) → ISNATILIST(nil)
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(n__zeros, y1)) → U411(isNat(zeros), activate(y1))
ISNATILIST(n__cons(n__0, y1)) → U411(isNat(0), activate(y1))
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(s(x0)), activate(y1))
ISNATILIST(n__cons(n__cons(x0, x1), y1)) → U411(isNat(cons(x0, x1)), activate(y1))
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
U411(tt, n__zeros) → ISNATILIST(n__zeros)

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(96) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(97) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATILIST(n__cons(n__zeros, y1)) → U411(isNat(zeros), activate(y1))
U411(tt, n__0) → ISNATILIST(0)
ISNATILIST(n__cons(n__0, y1)) → U411(isNat(0), activate(y1))
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__s(x0)) → ISNATILIST(s(x0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(s(x0)), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(cons(x0, x1))
ISNATILIST(n__cons(n__cons(x0, x1), y1)) → U411(isNat(cons(x0, x1)), activate(y1))
U411(tt, n__nil) → ISNATILIST(nil)
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(98) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATILIST(n__cons(n__zeros, y1)) → U411(isNat(zeros), activate(y1)) at position [0] we obtained the following new rules [LPAR04]:

ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(n__zeros), activate(y0))

(99) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, n__0) → ISNATILIST(0)
ISNATILIST(n__cons(n__0, y1)) → U411(isNat(0), activate(y1))
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__s(x0)) → ISNATILIST(s(x0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(s(x0)), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(cons(x0, x1))
ISNATILIST(n__cons(n__cons(x0, x1), y1)) → U411(isNat(cons(x0, x1)), activate(y1))
U411(tt, n__nil) → ISNATILIST(nil)
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(n__zeros), activate(y0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(100) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(101) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATILIST(n__cons(n__0, y1)) → U411(isNat(0), activate(y1))
U411(tt, n__0) → ISNATILIST(0)
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(s(x0)), activate(y1))
U411(tt, n__s(x0)) → ISNATILIST(s(x0))
ISNATILIST(n__cons(n__cons(x0, x1), y1)) → U411(isNat(cons(x0, x1)), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(cons(x0, x1))
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
U411(tt, n__nil) → ISNATILIST(nil)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(102) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATILIST(n__cons(n__0, y1)) → U411(isNat(0), activate(y1)) at position [0] we obtained the following new rules [LPAR04]:

ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))

(103) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, n__0) → ISNATILIST(0)
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(s(x0)), activate(y1))
U411(tt, n__s(x0)) → ISNATILIST(s(x0))
ISNATILIST(n__cons(n__cons(x0, x1), y1)) → U411(isNat(cons(x0, x1)), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(cons(x0, x1))
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
U411(tt, n__nil) → ISNATILIST(nil)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(104) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U411(tt, n__0) → ISNATILIST(0) at position [0] we obtained the following new rules [LPAR04]:

U411(tt, n__0) → ISNATILIST(n__0)

(105) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(s(x0)), activate(y1))
U411(tt, n__s(x0)) → ISNATILIST(s(x0))
ISNATILIST(n__cons(n__cons(x0, x1), y1)) → U411(isNat(cons(x0, x1)), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(cons(x0, x1))
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
U411(tt, n__nil) → ISNATILIST(nil)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
U411(tt, n__0) → ISNATILIST(n__0)

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(106) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(107) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__s(x0)) → ISNATILIST(s(x0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(s(x0)), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(cons(x0, x1))
ISNATILIST(n__cons(n__cons(x0, x1), y1)) → U411(isNat(cons(x0, x1)), activate(y1))
U411(tt, n__nil) → ISNATILIST(nil)
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(108) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U411(tt, n__s(x0)) → ISNATILIST(s(x0)) at position [0] we obtained the following new rules [LPAR04]:

U411(tt, n__s(x0)) → ISNATILIST(n__s(x0))

(109) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(s(x0)), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(cons(x0, x1))
ISNATILIST(n__cons(n__cons(x0, x1), y1)) → U411(isNat(cons(x0, x1)), activate(y1))
U411(tt, n__nil) → ISNATILIST(nil)
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
U411(tt, n__s(x0)) → ISNATILIST(n__s(x0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(110) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(111) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(s(x0)), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(cons(x0, x1))
ISNATILIST(n__cons(n__cons(x0, x1), y1)) → U411(isNat(cons(x0, x1)), activate(y1))
U411(tt, n__nil) → ISNATILIST(nil)
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(112) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(s(x0)), activate(y1)) at position [0] we obtained the following new rules [LPAR04]:

ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))

(113) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
U411(tt, n__cons(x0, x1)) → ISNATILIST(cons(x0, x1))
ISNATILIST(n__cons(n__cons(x0, x1), y1)) → U411(isNat(cons(x0, x1)), activate(y1))
U411(tt, n__nil) → ISNATILIST(nil)
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(114) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U411(tt, n__cons(x0, x1)) → ISNATILIST(cons(x0, x1)) at position [0] we obtained the following new rules [LPAR04]:

U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))

(115) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__cons(x0, x1), y1)) → U411(isNat(cons(x0, x1)), activate(y1))
U411(tt, n__nil) → ISNATILIST(nil)
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(116) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATILIST(n__cons(n__cons(x0, x1), y1)) → U411(isNat(cons(x0, x1)), activate(y1)) at position [0] we obtained the following new rules [LPAR04]:

ISNATILIST(n__cons(n__cons(x0, x1), y2)) → U411(isNat(n__cons(x0, x1)), activate(y2))

(117) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
U411(tt, n__nil) → ISNATILIST(nil)
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__cons(x0, x1), y2)) → U411(isNat(n__cons(x0, x1)), activate(y2))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(118) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(119) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__nil) → ISNATILIST(nil)
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(120) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U411(tt, n__nil) → ISNATILIST(nil) at position [0] we obtained the following new rules [LPAR04]:

U411(tt, n__nil) → ISNATILIST(n__nil)

(121) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))
U411(tt, n__nil) → ISNATILIST(n__nil)

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(122) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(123) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(124) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATILIST(n__cons(n__nil, y1)) → U411(isNat(nil), activate(y1)) at position [0] we obtained the following new rules [LPAR04]:

ISNATILIST(n__cons(n__nil, y0)) → U411(isNat(n__nil), activate(y0))

(125) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))
ISNATILIST(n__cons(n__nil, y0)) → U411(isNat(n__nil), activate(y0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(126) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(127) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(128) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U411(tt, n__zeros) → ISNATILIST(cons(0, n__zeros)) at position [0] we obtained the following new rules [LPAR04]:

U411(tt, n__zeros) → ISNATILIST(n__cons(0, n__zeros))
U411(tt, n__zeros) → ISNATILIST(cons(n__0, n__zeros))

(129) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))
U411(tt, n__zeros) → ISNATILIST(n__cons(0, n__zeros))
U411(tt, n__zeros) → ISNATILIST(cons(n__0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(130) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(0, n__zeros)), activate(y0)) at position [0] we obtained the following new rules [LPAR04]:

ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(n__cons(0, n__zeros)), activate(y0))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(n__0, n__zeros)), activate(y0))

(131) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))
U411(tt, n__zeros) → ISNATILIST(n__cons(0, n__zeros))
U411(tt, n__zeros) → ISNATILIST(cons(n__0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(n__cons(0, n__zeros)), activate(y0))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(n__0, n__zeros)), activate(y0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(132) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(133) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))
U411(tt, n__zeros) → ISNATILIST(n__cons(0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(n__0, n__zeros)), activate(y0))
U411(tt, n__zeros) → ISNATILIST(cons(n__0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(134) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(cons(n__0, n__zeros)), activate(y0)) at position [0] we obtained the following new rules [LPAR04]:

ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(n__cons(n__0, n__zeros)), activate(y0))

(135) Obligation:

Q DP problem:
The TRS P consists of the following rules:

ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))
U411(tt, n__zeros) → ISNATILIST(n__cons(0, n__zeros))
U411(tt, n__zeros) → ISNATILIST(cons(n__0, n__zeros))
ISNATILIST(n__cons(n__zeros, y0)) → U411(isNat(n__cons(n__0, n__zeros)), activate(y0))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(136) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.

(137) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
U411(tt, n__zeros) → ISNATILIST(n__cons(0, n__zeros))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))
U411(tt, n__zeros) → ISNATILIST(cons(n__0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(138) Narrowing (EQUIVALENT transformation)

By narrowing [LPAR04] the rule U411(tt, n__zeros) → ISNATILIST(cons(n__0, n__zeros)) at position [0] we obtained the following new rules [LPAR04]:

U411(tt, n__zeros) → ISNATILIST(n__cons(n__0, n__zeros))

(139) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, n__length(x0)) → ISNATILIST(length(x0))
ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
U411(tt, n__zeros) → ISNATILIST(n__cons(0, n__zeros))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))
U411(tt, n__zeros) → ISNATILIST(n__cons(n__0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(140) MRRProof (EQUIVALENT transformation)

By using the rule removal processor [LPAR04] with the following ordering, at least one Dependency Pair or term rewrite system rule of this QDP problem can be strictly oriented.
Strictly oriented dependency pairs:

ISNATILIST(n__cons(n__length(x0), y1)) → U411(isNat(length(x0)), activate(y1))


Used ordering: Polynomial interpretation [POLO]:

POL(0) = 0   
POL(ISNATILIST(x1)) = 2·x1   
POL(U21(x1)) = x1   
POL(U411(x1, x2)) = x1 + 2·x2   
POL(U51(x1, x2)) = x1 + 2·x2   
POL(U52(x1)) = 2·x1   
POL(U61(x1, x2, x3)) = 1 + x1 + 2·x2 + 2·x3   
POL(U62(x1, x2)) = 1 + x1 + 2·x2   
POL(activate(x1)) = x1   
POL(cons(x1, x2)) = x1 + 2·x2   
POL(isNat(x1)) = x1   
POL(isNatList(x1)) = x1   
POL(length(x1)) = 1 + 2·x1   
POL(n__0) = 0   
POL(n__cons(x1, x2)) = x1 + 2·x2   
POL(n__length(x1)) = 1 + 2·x1   
POL(n__nil) = 0   
POL(n__s(x1)) = x1   
POL(n__zeros) = 0   
POL(nil) = 0   
POL(s(x1)) = x1   
POL(tt) = 0   
POL(zeros) = 0   

(141) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, n__length(x0)) → ISNATILIST(length(x0))
U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
U411(tt, n__zeros) → ISNATILIST(n__cons(0, n__zeros))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))
U411(tt, n__zeros) → ISNATILIST(n__cons(n__0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(142) MRRProof (EQUIVALENT transformation)

By using the rule removal processor [LPAR04] with the following ordering, at least one Dependency Pair or term rewrite system rule of this QDP problem can be strictly oriented.
Strictly oriented dependency pairs:

U411(tt, n__length(x0)) → ISNATILIST(length(x0))


Used ordering: Polynomial interpretation [POLO]:

POL(0) = 0   
POL(ISNATILIST(x1)) = x1   
POL(U21(x1)) = x1   
POL(U411(x1, x2)) = 2·x1 + 2·x2   
POL(U51(x1, x2)) = 2·x1 + 2·x2   
POL(U52(x1)) = 2·x1   
POL(U61(x1, x2, x3)) = 1 + 2·x1 + 2·x2 + 2·x3   
POL(U62(x1, x2)) = 1 + 2·x1 + 2·x2   
POL(activate(x1)) = x1   
POL(cons(x1, x2)) = 2·x1 + 2·x2   
POL(isNat(x1)) = x1   
POL(isNatList(x1)) = x1   
POL(length(x1)) = 1 + 2·x1   
POL(n__0) = 0   
POL(n__cons(x1, x2)) = 2·x1 + 2·x2   
POL(n__length(x1)) = 1 + 2·x1   
POL(n__nil) = 0   
POL(n__s(x1)) = x1   
POL(n__zeros) = 0   
POL(nil) = 0   
POL(s(x1)) = x1   
POL(tt) = 0   
POL(zeros) = 0   

(143) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
U411(tt, n__zeros) → ISNATILIST(n__cons(0, n__zeros))
ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))
U411(tt, n__zeros) → ISNATILIST(n__cons(n__0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(144) QDPOrderProof (EQUIVALENT transformation)

We use the reduction pair processor [LPAR04,JAR06].


The following pairs can be oriented strictly and are deleted.


ISNATILIST(n__cons(n__s(x0), y1)) → U411(isNat(n__s(x0)), activate(y1))
The remaining pairs can at least be oriented weakly.
Used ordering: Polynomial interpretation [POLO]:

POL(0) = 0   
POL(ISNATILIST(x1)) = x1   
POL(U21(x1)) = 0   
POL(U411(x1, x2)) = x2   
POL(U51(x1, x2)) = 1 + x2   
POL(U52(x1)) = 1   
POL(U61(x1, x2, x3)) = 1 + x2   
POL(U62(x1, x2)) = 1 + x2   
POL(activate(x1)) = x1   
POL(cons(x1, x2)) = x1 + x2   
POL(isNat(x1)) = 1   
POL(isNatList(x1)) = 1 + x1   
POL(length(x1)) = 1 + x1   
POL(n__0) = 0   
POL(n__cons(x1, x2)) = x1 + x2   
POL(n__length(x1)) = 1 + x1   
POL(n__nil) = 0   
POL(n__s(x1)) = 1   
POL(n__zeros) = 0   
POL(nil) = 0   
POL(s(x1)) = 1   
POL(tt) = 0   
POL(zeros) = 0   

The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:

isNat(n__s(V1)) → U21(isNat(activate(V1)))
activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
0n__0
length(X) → n__length(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U21(tt) → tt
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
s(X) → n__s(X)
zeroscons(0, n__zeros)
zerosn__zeros
cons(X1, X2) → n__cons(X1, X2)
niln__nil

(145) Obligation:

Q DP problem:
The TRS P consists of the following rules:

U411(tt, x0) → ISNATILIST(x0)
ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))
U411(tt, n__cons(x0, x1)) → ISNATILIST(n__cons(x0, x1))
ISNATILIST(n__cons(n__0, y0)) → U411(isNat(n__0), activate(y0))
U411(tt, n__zeros) → ISNATILIST(n__cons(0, n__zeros))
U411(tt, n__zeros) → ISNATILIST(n__cons(n__0, n__zeros))

The TRS R consists of the following rules:

activate(n__zeros) → zeros
activate(n__0) → 0
activate(n__length(X)) → length(X)
activate(n__s(X)) → s(X)
activate(n__cons(X1, X2)) → cons(X1, X2)
activate(n__nil) → nil
activate(X) → X
isNat(n__0) → tt
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U21(tt) → tt
niln__nil
cons(X1, X2) → n__cons(X1, X2)
s(X) → n__s(X)
length(cons(N, L)) → U61(isNatList(activate(L)), activate(L), N)
length(X) → n__length(X)
isNatList(n__cons(V1, V2)) → U51(isNat(activate(V1)), activate(V2))
U61(tt, L, N) → U62(isNat(activate(N)), activate(L))
U62(tt, L) → s(length(activate(L)))
U51(tt, V2) → U52(isNatList(activate(V2)))
U52(tt) → tt
0n__0
zeroscons(0, n__zeros)
zerosn__zeros

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

(146) NonTerminationLoopProof (EQUIVALENT transformation)

We used the non-termination processor [FROCOS05] to show that the DP problem is infinite.
Found a loop by narrowing to the left:

s = U411(isNat(n__0), activate(n__zeros)) evaluates to t =U411(isNat(n__0), activate(n__zeros))

Thus s starts an infinite chain as s semiunifies with t with the following substitutions:
  • Matcher: [ ]
  • Semiunifier: [ ]




Rewriting sequence

U411(isNat(n__0), activate(n__zeros))U411(isNat(n__0), n__zeros)
with rule activate(X) → X at position [1] and matcher [X / n__zeros]

U411(isNat(n__0), n__zeros)U411(tt, n__zeros)
with rule isNat(n__0) → tt at position [0] and matcher [ ]

U411(tt, n__zeros)ISNATILIST(n__cons(n__0, n__zeros))
with rule U411(tt, n__zeros) → ISNATILIST(n__cons(n__0, n__zeros)) at position [] and matcher [ ]

ISNATILIST(n__cons(n__0, n__zeros))U411(isNat(n__0), activate(n__zeros))
with rule ISNATILIST(n__cons(x0, y1)) → U411(isNat(x0), activate(y1))

Now applying the matcher to the start term leads to a term which is equal to the last term in the rewriting sequence


All these steps are and every following step will be a correct step w.r.t to Q.



(147) NO