Termination w.r.t. Q of the following Term Rewriting System could be proven:

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

U11(tt, V2) → U12(isNat(activate(V2)))
U12(tt) → tt
U21(tt) → tt
U31(tt, N) → activate(N)
U41(tt, M, N) → U42(isNat(activate(N)), activate(M), activate(N))
U42(tt, M, N) → s(plus(activate(N), activate(M)))
isNat(n__0) → tt
isNat(n__plus(V1, V2)) → U11(isNat(activate(V1)), activate(V2))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
plus(N, 0) → U31(isNat(N), N)
plus(N, s(M)) → U41(isNat(M), M, N)
0n__0
plus(X1, X2) → n__plus(X1, X2)
s(X) → n__s(X)
activate(n__0) → 0
activate(n__plus(X1, X2)) → plus(X1, X2)
activate(n__s(X)) → s(X)
activate(X) → X

Q is empty.


QTRS
  ↳ DependencyPairsProof

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

U11(tt, V2) → U12(isNat(activate(V2)))
U12(tt) → tt
U21(tt) → tt
U31(tt, N) → activate(N)
U41(tt, M, N) → U42(isNat(activate(N)), activate(M), activate(N))
U42(tt, M, N) → s(plus(activate(N), activate(M)))
isNat(n__0) → tt
isNat(n__plus(V1, V2)) → U11(isNat(activate(V1)), activate(V2))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
plus(N, 0) → U31(isNat(N), N)
plus(N, s(M)) → U41(isNat(M), M, N)
0n__0
plus(X1, X2) → n__plus(X1, X2)
s(X) → n__s(X)
activate(n__0) → 0
activate(n__plus(X1, X2)) → plus(X1, X2)
activate(n__s(X)) → s(X)
activate(X) → X

Q is empty.

Using Dependency Pairs [1,15] we result in the following initial DP problem:
Q DP problem:
The TRS P consists of the following rules:

U111(tt, V2) → U121(isNat(activate(V2)))
ACTIVATE(n__plus(X1, X2)) → PLUS(X1, X2)
PLUS(N, s(M)) → ISNAT(M)
U421(tt, M, N) → PLUS(activate(N), activate(M))
U421(tt, M, N) → S(plus(activate(N), activate(M)))
U311(tt, N) → ACTIVATE(N)
ACTIVATE(n__0) → 01
U411(tt, M, N) → ISNAT(activate(N))
ISNAT(n__plus(V1, V2)) → U111(isNat(activate(V1)), activate(V2))
U411(tt, M, N) → ACTIVATE(N)
ISNAT(n__s(V1)) → U211(isNat(activate(V1)))
U111(tt, V2) → ACTIVATE(V2)
PLUS(N, 0) → ISNAT(N)
PLUS(N, 0) → U311(isNat(N), N)
U411(tt, M, N) → ACTIVATE(M)
U421(tt, M, N) → ACTIVATE(M)
ISNAT(n__s(V1)) → ISNAT(activate(V1))
ACTIVATE(n__s(X)) → S(X)
ISNAT(n__plus(V1, V2)) → ACTIVATE(V2)
ISNAT(n__s(V1)) → ACTIVATE(V1)
U411(tt, M, N) → U421(isNat(activate(N)), activate(M), activate(N))
ISNAT(n__plus(V1, V2)) → ACTIVATE(V1)
PLUS(N, s(M)) → U411(isNat(M), M, N)
U111(tt, V2) → ISNAT(activate(V2))
ISNAT(n__plus(V1, V2)) → ISNAT(activate(V1))
U421(tt, M, N) → ACTIVATE(N)

The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(activate(V2)))
U12(tt) → tt
U21(tt) → tt
U31(tt, N) → activate(N)
U41(tt, M, N) → U42(isNat(activate(N)), activate(M), activate(N))
U42(tt, M, N) → s(plus(activate(N), activate(M)))
isNat(n__0) → tt
isNat(n__plus(V1, V2)) → U11(isNat(activate(V1)), activate(V2))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
plus(N, 0) → U31(isNat(N), N)
plus(N, s(M)) → U41(isNat(M), M, N)
0n__0
plus(X1, X2) → n__plus(X1, X2)
s(X) → n__s(X)
activate(n__0) → 0
activate(n__plus(X1, X2)) → plus(X1, X2)
activate(n__s(X)) → s(X)
activate(X) → X

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

↳ QTRS
  ↳ DependencyPairsProof
QDP
      ↳ DependencyGraphProof

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

U111(tt, V2) → U121(isNat(activate(V2)))
ACTIVATE(n__plus(X1, X2)) → PLUS(X1, X2)
PLUS(N, s(M)) → ISNAT(M)
U421(tt, M, N) → PLUS(activate(N), activate(M))
U421(tt, M, N) → S(plus(activate(N), activate(M)))
U311(tt, N) → ACTIVATE(N)
ACTIVATE(n__0) → 01
U411(tt, M, N) → ISNAT(activate(N))
ISNAT(n__plus(V1, V2)) → U111(isNat(activate(V1)), activate(V2))
U411(tt, M, N) → ACTIVATE(N)
ISNAT(n__s(V1)) → U211(isNat(activate(V1)))
U111(tt, V2) → ACTIVATE(V2)
PLUS(N, 0) → ISNAT(N)
PLUS(N, 0) → U311(isNat(N), N)
U411(tt, M, N) → ACTIVATE(M)
U421(tt, M, N) → ACTIVATE(M)
ISNAT(n__s(V1)) → ISNAT(activate(V1))
ACTIVATE(n__s(X)) → S(X)
ISNAT(n__plus(V1, V2)) → ACTIVATE(V2)
ISNAT(n__s(V1)) → ACTIVATE(V1)
U411(tt, M, N) → U421(isNat(activate(N)), activate(M), activate(N))
ISNAT(n__plus(V1, V2)) → ACTIVATE(V1)
PLUS(N, s(M)) → U411(isNat(M), M, N)
U111(tt, V2) → ISNAT(activate(V2))
ISNAT(n__plus(V1, V2)) → ISNAT(activate(V1))
U421(tt, M, N) → ACTIVATE(N)

The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(activate(V2)))
U12(tt) → tt
U21(tt) → tt
U31(tt, N) → activate(N)
U41(tt, M, N) → U42(isNat(activate(N)), activate(M), activate(N))
U42(tt, M, N) → s(plus(activate(N), activate(M)))
isNat(n__0) → tt
isNat(n__plus(V1, V2)) → U11(isNat(activate(V1)), activate(V2))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
plus(N, 0) → U31(isNat(N), N)
plus(N, s(M)) → U41(isNat(M), M, N)
0n__0
plus(X1, X2) → n__plus(X1, X2)
s(X) → n__s(X)
activate(n__0) → 0
activate(n__plus(X1, X2)) → plus(X1, X2)
activate(n__s(X)) → s(X)
activate(X) → X

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
The approximation of the Dependency Graph [15,17,22] contains 1 SCC with 5 less nodes.

↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof
QDP
          ↳ QDPOrderProof

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

PLUS(N, 0) → U311(isNat(N), N)
U411(tt, M, N) → ACTIVATE(M)
ACTIVATE(n__plus(X1, X2)) → PLUS(X1, X2)
U421(tt, M, N) → ACTIVATE(M)
PLUS(N, s(M)) → ISNAT(M)
ISNAT(n__s(V1)) → ISNAT(activate(V1))
ISNAT(n__plus(V1, V2)) → ACTIVATE(V2)
ISNAT(n__s(V1)) → ACTIVATE(V1)
U421(tt, M, N) → PLUS(activate(N), activate(M))
U411(tt, M, N) → U421(isNat(activate(N)), activate(M), activate(N))
U311(tt, N) → ACTIVATE(N)
ISNAT(n__plus(V1, V2)) → ACTIVATE(V1)
PLUS(N, s(M)) → U411(isNat(M), M, N)
U111(tt, V2) → ISNAT(activate(V2))
U411(tt, M, N) → ISNAT(activate(N))
U411(tt, M, N) → ACTIVATE(N)
ISNAT(n__plus(V1, V2)) → U111(isNat(activate(V1)), activate(V2))
U111(tt, V2) → ACTIVATE(V2)
PLUS(N, 0) → ISNAT(N)
ISNAT(n__plus(V1, V2)) → ISNAT(activate(V1))
U421(tt, M, N) → ACTIVATE(N)

The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(activate(V2)))
U12(tt) → tt
U21(tt) → tt
U31(tt, N) → activate(N)
U41(tt, M, N) → U42(isNat(activate(N)), activate(M), activate(N))
U42(tt, M, N) → s(plus(activate(N), activate(M)))
isNat(n__0) → tt
isNat(n__plus(V1, V2)) → U11(isNat(activate(V1)), activate(V2))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
plus(N, 0) → U31(isNat(N), N)
plus(N, s(M)) → U41(isNat(M), M, N)
0n__0
plus(X1, X2) → n__plus(X1, X2)
s(X) → n__s(X)
activate(n__0) → 0
activate(n__plus(X1, X2)) → plus(X1, X2)
activate(n__s(X)) → s(X)
activate(X) → X

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
We use the reduction pair processor [15].


The following pairs can be oriented strictly and are deleted.


U411(tt, M, N) → ACTIVATE(M)
ACTIVATE(n__plus(X1, X2)) → PLUS(X1, X2)
U421(tt, M, N) → ACTIVATE(M)
PLUS(N, s(M)) → ISNAT(M)
ISNAT(n__plus(V1, V2)) → ACTIVATE(V2)
U311(tt, N) → ACTIVATE(N)
ISNAT(n__plus(V1, V2)) → ACTIVATE(V1)
U111(tt, V2) → ISNAT(activate(V2))
U411(tt, M, N) → ISNAT(activate(N))
U411(tt, M, N) → ACTIVATE(N)
U111(tt, V2) → ACTIVATE(V2)
PLUS(N, 0) → ISNAT(N)
ISNAT(n__plus(V1, V2)) → ISNAT(activate(V1))
U421(tt, M, N) → ACTIVATE(N)
The remaining pairs can at least be oriented weakly.

PLUS(N, 0) → U311(isNat(N), N)
ISNAT(n__s(V1)) → ISNAT(activate(V1))
ISNAT(n__s(V1)) → ACTIVATE(V1)
U421(tt, M, N) → PLUS(activate(N), activate(M))
U411(tt, M, N) → U421(isNat(activate(N)), activate(M), activate(N))
PLUS(N, s(M)) → U411(isNat(M), M, N)
ISNAT(n__plus(V1, V2)) → U111(isNat(activate(V1)), activate(V2))
Used ordering: Polynomial interpretation [25,35]:

POL(n__plus(x1, x2)) = 2 + x_1 + (2)x_2   
POL(plus(x1, x2)) = 2 + x_1 + (2)x_2   
POL(U421(x1, x2, x3)) = 1 + x_2 + x_3   
POL(U31(x1, x2)) = 2 + x_2   
POL(U41(x1, x2, x3)) = 2 + (2)x_2 + x_3   
POL(activate(x1)) = x_1   
POL(U11(x1, x2)) = 0   
POL(n__s(x1)) = x_1   
POL(0) = 0   
POL(U411(x1, x2, x3)) = 1 + x_2 + x_3   
POL(ISNAT(x1)) = x_1   
POL(PLUS(x1, x2)) = 1 + x_1 + x_2   
POL(tt) = 0   
POL(U111(x1, x2)) = 2 + (2)x_2   
POL(U42(x1, x2, x3)) = 2 + (2)x_2 + x_3   
POL(U311(x1, x2)) = 1 + x_2   
POL(n__0) = 0   
POL(U12(x1)) = 0   
POL(s(x1)) = x_1   
POL(isNat(x1)) = 0   
POL(ACTIVATE(x1)) = x_1   
POL(U21(x1)) = 0   
The value of delta used in the strict ordering is 1.
The following usable rules [17] were oriented:

isNat(n__plus(V1, V2)) → U11(isNat(activate(V1)), activate(V2))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U42(tt, M, N) → s(plus(activate(N), activate(M)))
0n__0
plus(X1, X2) → n__plus(X1, X2)
plus(N, s(M)) → U41(isNat(M), M, N)
activate(n__plus(X1, X2)) → plus(X1, X2)
plus(N, 0) → U31(isNat(N), N)
U31(tt, N) → activate(N)
activate(n__s(X)) → s(X)
s(X) → n__s(X)
activate(n__0) → 0
activate(X) → X
U11(tt, V2) → U12(isNat(activate(V2)))
U21(tt) → tt
U12(tt) → tt
U41(tt, M, N) → U42(isNat(activate(N)), activate(M), activate(N))



↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof
        ↳ QDP
          ↳ QDPOrderProof
QDP
              ↳ DependencyGraphProof

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

PLUS(N, 0) → U311(isNat(N), N)
PLUS(N, s(M)) → U411(isNat(M), M, N)
ISNAT(n__s(V1)) → ISNAT(activate(V1))
ISNAT(n__plus(V1, V2)) → U111(isNat(activate(V1)), activate(V2))
ISNAT(n__s(V1)) → ACTIVATE(V1)
U411(tt, M, N) → U421(isNat(activate(N)), activate(M), activate(N))
U421(tt, M, N) → PLUS(activate(N), activate(M))

The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(activate(V2)))
U12(tt) → tt
U21(tt) → tt
U31(tt, N) → activate(N)
U41(tt, M, N) → U42(isNat(activate(N)), activate(M), activate(N))
U42(tt, M, N) → s(plus(activate(N), activate(M)))
isNat(n__0) → tt
isNat(n__plus(V1, V2)) → U11(isNat(activate(V1)), activate(V2))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
plus(N, 0) → U31(isNat(N), N)
plus(N, s(M)) → U41(isNat(M), M, N)
0n__0
plus(X1, X2) → n__plus(X1, X2)
s(X) → n__s(X)
activate(n__0) → 0
activate(n__plus(X1, X2)) → plus(X1, X2)
activate(n__s(X)) → s(X)
activate(X) → X

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
The approximation of the Dependency Graph [15,17,22] contains 2 SCCs with 3 less nodes.

↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof
        ↳ QDP
          ↳ QDPOrderProof
            ↳ QDP
              ↳ DependencyGraphProof
                ↳ AND
QDP
                    ↳ QDPOrderProof
                  ↳ QDP

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:

U11(tt, V2) → U12(isNat(activate(V2)))
U12(tt) → tt
U21(tt) → tt
U31(tt, N) → activate(N)
U41(tt, M, N) → U42(isNat(activate(N)), activate(M), activate(N))
U42(tt, M, N) → s(plus(activate(N), activate(M)))
isNat(n__0) → tt
isNat(n__plus(V1, V2)) → U11(isNat(activate(V1)), activate(V2))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
plus(N, 0) → U31(isNat(N), N)
plus(N, s(M)) → U41(isNat(M), M, N)
0n__0
plus(X1, X2) → n__plus(X1, X2)
s(X) → n__s(X)
activate(n__0) → 0
activate(n__plus(X1, X2)) → plus(X1, X2)
activate(n__s(X)) → s(X)
activate(X) → X

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
We use the reduction pair processor [15].


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.
none
Used ordering: Polynomial interpretation [25,35]:

POL(n__plus(x1, x2)) = x_1 + (4)x_2   
POL(plus(x1, x2)) = x_1 + (4)x_2   
POL(U31(x1, x2)) = x_2   
POL(U41(x1, x2, x3)) = 1 + (4)x_2 + x_3   
POL(activate(x1)) = x_1   
POL(n__s(x1)) = 1 + x_1   
POL(U11(x1, x2)) = 4   
POL(0) = 0   
POL(ISNAT(x1)) = (4)x_1   
POL(tt) = 2   
POL(U42(x1, x2, x3)) = 1 + (4)x_2 + x_3   
POL(n__0) = 0   
POL(U12(x1)) = 4   
POL(s(x1)) = 1 + x_1   
POL(isNat(x1)) = 4   
POL(U21(x1)) = 4   
The value of delta used in the strict ordering is 4.
The following usable rules [17] were oriented:

isNat(n__plus(V1, V2)) → U11(isNat(activate(V1)), activate(V2))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U42(tt, M, N) → s(plus(activate(N), activate(M)))
0n__0
plus(X1, X2) → n__plus(X1, X2)
plus(N, s(M)) → U41(isNat(M), M, N)
activate(n__plus(X1, X2)) → plus(X1, X2)
plus(N, 0) → U31(isNat(N), N)
U31(tt, N) → activate(N)
activate(n__s(X)) → s(X)
s(X) → n__s(X)
activate(n__0) → 0
activate(X) → X
U11(tt, V2) → U12(isNat(activate(V2)))
U21(tt) → tt
U12(tt) → tt
U41(tt, M, N) → U42(isNat(activate(N)), activate(M), activate(N))



↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof
        ↳ QDP
          ↳ QDPOrderProof
            ↳ QDP
              ↳ DependencyGraphProof
                ↳ AND
                  ↳ QDP
                    ↳ QDPOrderProof
QDP
                        ↳ PisEmptyProof
                  ↳ QDP

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

U11(tt, V2) → U12(isNat(activate(V2)))
U12(tt) → tt
U21(tt) → tt
U31(tt, N) → activate(N)
U41(tt, M, N) → U42(isNat(activate(N)), activate(M), activate(N))
U42(tt, M, N) → s(plus(activate(N), activate(M)))
isNat(n__0) → tt
isNat(n__plus(V1, V2)) → U11(isNat(activate(V1)), activate(V2))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
plus(N, 0) → U31(isNat(N), N)
plus(N, s(M)) → U41(isNat(M), M, N)
0n__0
plus(X1, X2) → n__plus(X1, X2)
s(X) → n__s(X)
activate(n__0) → 0
activate(n__plus(X1, X2)) → plus(X1, X2)
activate(n__s(X)) → s(X)
activate(X) → X

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
The TRS P is empty. Hence, there is no (P,Q,R) chain.

↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof
        ↳ QDP
          ↳ QDPOrderProof
            ↳ QDP
              ↳ DependencyGraphProof
                ↳ AND
                  ↳ QDP
QDP
                    ↳ QDPOrderProof

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

PLUS(N, s(M)) → U411(isNat(M), M, N)
U421(tt, M, N) → PLUS(activate(N), activate(M))
U411(tt, M, N) → U421(isNat(activate(N)), activate(M), activate(N))

The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(activate(V2)))
U12(tt) → tt
U21(tt) → tt
U31(tt, N) → activate(N)
U41(tt, M, N) → U42(isNat(activate(N)), activate(M), activate(N))
U42(tt, M, N) → s(plus(activate(N), activate(M)))
isNat(n__0) → tt
isNat(n__plus(V1, V2)) → U11(isNat(activate(V1)), activate(V2))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
plus(N, 0) → U31(isNat(N), N)
plus(N, s(M)) → U41(isNat(M), M, N)
0n__0
plus(X1, X2) → n__plus(X1, X2)
s(X) → n__s(X)
activate(n__0) → 0
activate(n__plus(X1, X2)) → plus(X1, X2)
activate(n__s(X)) → s(X)
activate(X) → X

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
We use the reduction pair processor [15].


The following pairs can be oriented strictly and are deleted.


PLUS(N, s(M)) → U411(isNat(M), M, N)
The remaining pairs can at least be oriented weakly.

U421(tt, M, N) → PLUS(activate(N), activate(M))
U411(tt, M, N) → U421(isNat(activate(N)), activate(M), activate(N))
Used ordering: Polynomial interpretation [25,35]:

POL(n__plus(x1, x2)) = (4)x_1 + x_2   
POL(plus(x1, x2)) = (4)x_1 + x_2   
POL(U421(x1, x2, x3)) = 4 + (3)x_2   
POL(U31(x1, x2)) = (4)x_2   
POL(U41(x1, x2, x3)) = 4 + x_2 + (4)x_3   
POL(activate(x1)) = x_1   
POL(U11(x1, x2)) = 0   
POL(n__s(x1)) = 4 + x_1   
POL(0) = 0   
POL(U411(x1, x2, x3)) = 4 + (3)x_2   
POL(PLUS(x1, x2)) = 4 + (3)x_2   
POL(tt) = 0   
POL(U42(x1, x2, x3)) = 4 + x_2 + (4)x_3   
POL(n__0) = 0   
POL(U12(x1)) = 0   
POL(s(x1)) = 4 + x_1   
POL(isNat(x1)) = 0   
POL(U21(x1)) = 0   
The value of delta used in the strict ordering is 12.
The following usable rules [17] were oriented:

isNat(n__plus(V1, V2)) → U11(isNat(activate(V1)), activate(V2))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
U42(tt, M, N) → s(plus(activate(N), activate(M)))
0n__0
plus(X1, X2) → n__plus(X1, X2)
plus(N, s(M)) → U41(isNat(M), M, N)
activate(n__plus(X1, X2)) → plus(X1, X2)
plus(N, 0) → U31(isNat(N), N)
U31(tt, N) → activate(N)
activate(n__s(X)) → s(X)
s(X) → n__s(X)
activate(n__0) → 0
activate(X) → X
U11(tt, V2) → U12(isNat(activate(V2)))
U21(tt) → tt
U12(tt) → tt
U41(tt, M, N) → U42(isNat(activate(N)), activate(M), activate(N))



↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof
        ↳ QDP
          ↳ QDPOrderProof
            ↳ QDP
              ↳ DependencyGraphProof
                ↳ AND
                  ↳ QDP
                  ↳ QDP
                    ↳ QDPOrderProof
QDP
                        ↳ DependencyGraphProof

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

U411(tt, M, N) → U421(isNat(activate(N)), activate(M), activate(N))
U421(tt, M, N) → PLUS(activate(N), activate(M))

The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(activate(V2)))
U12(tt) → tt
U21(tt) → tt
U31(tt, N) → activate(N)
U41(tt, M, N) → U42(isNat(activate(N)), activate(M), activate(N))
U42(tt, M, N) → s(plus(activate(N), activate(M)))
isNat(n__0) → tt
isNat(n__plus(V1, V2)) → U11(isNat(activate(V1)), activate(V2))
isNat(n__s(V1)) → U21(isNat(activate(V1)))
plus(N, 0) → U31(isNat(N), N)
plus(N, s(M)) → U41(isNat(M), M, N)
0n__0
plus(X1, X2) → n__plus(X1, X2)
s(X) → n__s(X)
activate(n__0) → 0
activate(n__plus(X1, X2)) → plus(X1, X2)
activate(n__s(X)) → s(X)
activate(X) → X

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
The approximation of the Dependency Graph [15,17,22] contains 0 SCCs with 2 less nodes.