Left Termination of the query pattern goal() w.r.t. the given Prolog program could successfully be proven:



PROLOG
  ↳ PrologToPiTRSProof

even1(s12 (X)) :- even1(X).
even1(00).
lte2(s1(X), s1(Y)) :- lte2(X, Y).
lte2(00, Y).
goal0 :- lte2(X, s14 (00)), even1(X).


With regard to the inferred argument filtering the predicates were used in the following modes:
lte2: (f,b)
even1: (b)
Transforming PROLOG into the following Term Rewriting System:
Pi-finite rewrite system:
The TRS R consists of the following rules:


goal_0_in_ -> if_goal_0_in_1_1(lte_2_in_ag2(X, s_11(s_11(s_11(s_11(0_0))))))
lte_2_in_ag2(s_11(X), s_11(Y)) -> if_lte_2_in_1_ag3(X, Y, lte_2_in_ag2(X, Y))
lte_2_in_ag2(0_0, Y) -> lte_2_out_ag2(0_0, Y)
if_lte_2_in_1_ag3(X, Y, lte_2_out_ag2(X, Y)) -> lte_2_out_ag2(s_11(X), s_11(Y))
if_goal_0_in_1_1(lte_2_out_ag2(X, s_11(s_11(s_11(s_11(0_0)))))) -> if_goal_0_in_2_2(X, even_1_in_g1(X))
even_1_in_g1(s_11(s_11(X))) -> if_even_1_in_1_g2(X, even_1_in_g1(X))
even_1_in_g1(0_0) -> even_1_out_g1(0_0)
if_even_1_in_1_g2(X, even_1_out_g1(X)) -> even_1_out_g1(s_11(s_11(X)))
if_goal_0_in_2_2(X, even_1_out_g1(X)) -> goal_0_out_

The argument filtering Pi contains the following mapping:
goal_0_in_  =  goal_0_in_
s_11(x1)  =  s_11(x1)
0_0  =  0_0
if_goal_0_in_1_1(x1)  =  if_goal_0_in_1_1(x1)
lte_2_in_ag2(x1, x2)  =  lte_2_in_ag1(x2)
if_lte_2_in_1_ag3(x1, x2, x3)  =  if_lte_2_in_1_ag1(x3)
lte_2_out_ag2(x1, x2)  =  lte_2_out_ag1(x1)
if_goal_0_in_2_2(x1, x2)  =  if_goal_0_in_2_1(x2)
even_1_in_g1(x1)  =  even_1_in_g1(x1)
if_even_1_in_1_g2(x1, x2)  =  if_even_1_in_1_g1(x2)
even_1_out_g1(x1)  =  even_1_out_g
goal_0_out_  =  goal_0_out_

Infinitary Constructor Rewriting Termination of PiTRS implies Termination of PROLOG



↳ PROLOG
  ↳ PrologToPiTRSProof
PiTRS
      ↳ DependencyPairsProof

Pi-finite rewrite system:
The TRS R consists of the following rules:

goal_0_in_ -> if_goal_0_in_1_1(lte_2_in_ag2(X, s_11(s_11(s_11(s_11(0_0))))))
lte_2_in_ag2(s_11(X), s_11(Y)) -> if_lte_2_in_1_ag3(X, Y, lte_2_in_ag2(X, Y))
lte_2_in_ag2(0_0, Y) -> lte_2_out_ag2(0_0, Y)
if_lte_2_in_1_ag3(X, Y, lte_2_out_ag2(X, Y)) -> lte_2_out_ag2(s_11(X), s_11(Y))
if_goal_0_in_1_1(lte_2_out_ag2(X, s_11(s_11(s_11(s_11(0_0)))))) -> if_goal_0_in_2_2(X, even_1_in_g1(X))
even_1_in_g1(s_11(s_11(X))) -> if_even_1_in_1_g2(X, even_1_in_g1(X))
even_1_in_g1(0_0) -> even_1_out_g1(0_0)
if_even_1_in_1_g2(X, even_1_out_g1(X)) -> even_1_out_g1(s_11(s_11(X)))
if_goal_0_in_2_2(X, even_1_out_g1(X)) -> goal_0_out_

The argument filtering Pi contains the following mapping:
goal_0_in_  =  goal_0_in_
s_11(x1)  =  s_11(x1)
0_0  =  0_0
if_goal_0_in_1_1(x1)  =  if_goal_0_in_1_1(x1)
lte_2_in_ag2(x1, x2)  =  lte_2_in_ag1(x2)
if_lte_2_in_1_ag3(x1, x2, x3)  =  if_lte_2_in_1_ag1(x3)
lte_2_out_ag2(x1, x2)  =  lte_2_out_ag1(x1)
if_goal_0_in_2_2(x1, x2)  =  if_goal_0_in_2_1(x2)
even_1_in_g1(x1)  =  even_1_in_g1(x1)
if_even_1_in_1_g2(x1, x2)  =  if_even_1_in_1_g1(x2)
even_1_out_g1(x1)  =  even_1_out_g
goal_0_out_  =  goal_0_out_


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

GOAL_0_IN_ -> IF_GOAL_0_IN_1_1(lte_2_in_ag2(X, s_11(s_11(s_11(s_11(0_0))))))
GOAL_0_IN_ -> LTE_2_IN_AG2(X, s_11(s_11(s_11(s_11(0_0)))))
LTE_2_IN_AG2(s_11(X), s_11(Y)) -> IF_LTE_2_IN_1_AG3(X, Y, lte_2_in_ag2(X, Y))
LTE_2_IN_AG2(s_11(X), s_11(Y)) -> LTE_2_IN_AG2(X, Y)
IF_GOAL_0_IN_1_1(lte_2_out_ag2(X, s_11(s_11(s_11(s_11(0_0)))))) -> IF_GOAL_0_IN_2_2(X, even_1_in_g1(X))
IF_GOAL_0_IN_1_1(lte_2_out_ag2(X, s_11(s_11(s_11(s_11(0_0)))))) -> EVEN_1_IN_G1(X)
EVEN_1_IN_G1(s_11(s_11(X))) -> IF_EVEN_1_IN_1_G2(X, even_1_in_g1(X))
EVEN_1_IN_G1(s_11(s_11(X))) -> EVEN_1_IN_G1(X)

The TRS R consists of the following rules:

goal_0_in_ -> if_goal_0_in_1_1(lte_2_in_ag2(X, s_11(s_11(s_11(s_11(0_0))))))
lte_2_in_ag2(s_11(X), s_11(Y)) -> if_lte_2_in_1_ag3(X, Y, lte_2_in_ag2(X, Y))
lte_2_in_ag2(0_0, Y) -> lte_2_out_ag2(0_0, Y)
if_lte_2_in_1_ag3(X, Y, lte_2_out_ag2(X, Y)) -> lte_2_out_ag2(s_11(X), s_11(Y))
if_goal_0_in_1_1(lte_2_out_ag2(X, s_11(s_11(s_11(s_11(0_0)))))) -> if_goal_0_in_2_2(X, even_1_in_g1(X))
even_1_in_g1(s_11(s_11(X))) -> if_even_1_in_1_g2(X, even_1_in_g1(X))
even_1_in_g1(0_0) -> even_1_out_g1(0_0)
if_even_1_in_1_g2(X, even_1_out_g1(X)) -> even_1_out_g1(s_11(s_11(X)))
if_goal_0_in_2_2(X, even_1_out_g1(X)) -> goal_0_out_

The argument filtering Pi contains the following mapping:
goal_0_in_  =  goal_0_in_
s_11(x1)  =  s_11(x1)
0_0  =  0_0
if_goal_0_in_1_1(x1)  =  if_goal_0_in_1_1(x1)
lte_2_in_ag2(x1, x2)  =  lte_2_in_ag1(x2)
if_lte_2_in_1_ag3(x1, x2, x3)  =  if_lte_2_in_1_ag1(x3)
lte_2_out_ag2(x1, x2)  =  lte_2_out_ag1(x1)
if_goal_0_in_2_2(x1, x2)  =  if_goal_0_in_2_1(x2)
even_1_in_g1(x1)  =  even_1_in_g1(x1)
if_even_1_in_1_g2(x1, x2)  =  if_even_1_in_1_g1(x2)
even_1_out_g1(x1)  =  even_1_out_g
goal_0_out_  =  goal_0_out_
LTE_2_IN_AG2(x1, x2)  =  LTE_2_IN_AG1(x2)
IF_LTE_2_IN_1_AG3(x1, x2, x3)  =  IF_LTE_2_IN_1_AG1(x3)
IF_GOAL_0_IN_2_2(x1, x2)  =  IF_GOAL_0_IN_2_1(x2)
IF_GOAL_0_IN_1_1(x1)  =  IF_GOAL_0_IN_1_1(x1)
IF_EVEN_1_IN_1_G2(x1, x2)  =  IF_EVEN_1_IN_1_G1(x2)
EVEN_1_IN_G1(x1)  =  EVEN_1_IN_G1(x1)
GOAL_0_IN_  =  GOAL_0_IN_

We have to consider all (P,R,Pi)-chains

↳ PROLOG
  ↳ PrologToPiTRSProof
    ↳ PiTRS
      ↳ DependencyPairsProof
PiDP
          ↳ DependencyGraphProof

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

GOAL_0_IN_ -> IF_GOAL_0_IN_1_1(lte_2_in_ag2(X, s_11(s_11(s_11(s_11(0_0))))))
GOAL_0_IN_ -> LTE_2_IN_AG2(X, s_11(s_11(s_11(s_11(0_0)))))
LTE_2_IN_AG2(s_11(X), s_11(Y)) -> IF_LTE_2_IN_1_AG3(X, Y, lte_2_in_ag2(X, Y))
LTE_2_IN_AG2(s_11(X), s_11(Y)) -> LTE_2_IN_AG2(X, Y)
IF_GOAL_0_IN_1_1(lte_2_out_ag2(X, s_11(s_11(s_11(s_11(0_0)))))) -> IF_GOAL_0_IN_2_2(X, even_1_in_g1(X))
IF_GOAL_0_IN_1_1(lte_2_out_ag2(X, s_11(s_11(s_11(s_11(0_0)))))) -> EVEN_1_IN_G1(X)
EVEN_1_IN_G1(s_11(s_11(X))) -> IF_EVEN_1_IN_1_G2(X, even_1_in_g1(X))
EVEN_1_IN_G1(s_11(s_11(X))) -> EVEN_1_IN_G1(X)

The TRS R consists of the following rules:

goal_0_in_ -> if_goal_0_in_1_1(lte_2_in_ag2(X, s_11(s_11(s_11(s_11(0_0))))))
lte_2_in_ag2(s_11(X), s_11(Y)) -> if_lte_2_in_1_ag3(X, Y, lte_2_in_ag2(X, Y))
lte_2_in_ag2(0_0, Y) -> lte_2_out_ag2(0_0, Y)
if_lte_2_in_1_ag3(X, Y, lte_2_out_ag2(X, Y)) -> lte_2_out_ag2(s_11(X), s_11(Y))
if_goal_0_in_1_1(lte_2_out_ag2(X, s_11(s_11(s_11(s_11(0_0)))))) -> if_goal_0_in_2_2(X, even_1_in_g1(X))
even_1_in_g1(s_11(s_11(X))) -> if_even_1_in_1_g2(X, even_1_in_g1(X))
even_1_in_g1(0_0) -> even_1_out_g1(0_0)
if_even_1_in_1_g2(X, even_1_out_g1(X)) -> even_1_out_g1(s_11(s_11(X)))
if_goal_0_in_2_2(X, even_1_out_g1(X)) -> goal_0_out_

The argument filtering Pi contains the following mapping:
goal_0_in_  =  goal_0_in_
s_11(x1)  =  s_11(x1)
0_0  =  0_0
if_goal_0_in_1_1(x1)  =  if_goal_0_in_1_1(x1)
lte_2_in_ag2(x1, x2)  =  lte_2_in_ag1(x2)
if_lte_2_in_1_ag3(x1, x2, x3)  =  if_lte_2_in_1_ag1(x3)
lte_2_out_ag2(x1, x2)  =  lte_2_out_ag1(x1)
if_goal_0_in_2_2(x1, x2)  =  if_goal_0_in_2_1(x2)
even_1_in_g1(x1)  =  even_1_in_g1(x1)
if_even_1_in_1_g2(x1, x2)  =  if_even_1_in_1_g1(x2)
even_1_out_g1(x1)  =  even_1_out_g
goal_0_out_  =  goal_0_out_
LTE_2_IN_AG2(x1, x2)  =  LTE_2_IN_AG1(x2)
IF_LTE_2_IN_1_AG3(x1, x2, x3)  =  IF_LTE_2_IN_1_AG1(x3)
IF_GOAL_0_IN_2_2(x1, x2)  =  IF_GOAL_0_IN_2_1(x2)
IF_GOAL_0_IN_1_1(x1)  =  IF_GOAL_0_IN_1_1(x1)
IF_EVEN_1_IN_1_G2(x1, x2)  =  IF_EVEN_1_IN_1_G1(x2)
EVEN_1_IN_G1(x1)  =  EVEN_1_IN_G1(x1)
GOAL_0_IN_  =  GOAL_0_IN_

We have to consider all (P,R,Pi)-chains
The approximation of the Dependency Graph contains 2 SCCs with 6 less nodes.

↳ PROLOG
  ↳ PrologToPiTRSProof
    ↳ PiTRS
      ↳ DependencyPairsProof
        ↳ PiDP
          ↳ DependencyGraphProof
            ↳ AND
PiDP
                ↳ UsableRulesProof
              ↳ PiDP

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

EVEN_1_IN_G1(s_11(s_11(X))) -> EVEN_1_IN_G1(X)

The TRS R consists of the following rules:

goal_0_in_ -> if_goal_0_in_1_1(lte_2_in_ag2(X, s_11(s_11(s_11(s_11(0_0))))))
lte_2_in_ag2(s_11(X), s_11(Y)) -> if_lte_2_in_1_ag3(X, Y, lte_2_in_ag2(X, Y))
lte_2_in_ag2(0_0, Y) -> lte_2_out_ag2(0_0, Y)
if_lte_2_in_1_ag3(X, Y, lte_2_out_ag2(X, Y)) -> lte_2_out_ag2(s_11(X), s_11(Y))
if_goal_0_in_1_1(lte_2_out_ag2(X, s_11(s_11(s_11(s_11(0_0)))))) -> if_goal_0_in_2_2(X, even_1_in_g1(X))
even_1_in_g1(s_11(s_11(X))) -> if_even_1_in_1_g2(X, even_1_in_g1(X))
even_1_in_g1(0_0) -> even_1_out_g1(0_0)
if_even_1_in_1_g2(X, even_1_out_g1(X)) -> even_1_out_g1(s_11(s_11(X)))
if_goal_0_in_2_2(X, even_1_out_g1(X)) -> goal_0_out_

The argument filtering Pi contains the following mapping:
goal_0_in_  =  goal_0_in_
s_11(x1)  =  s_11(x1)
0_0  =  0_0
if_goal_0_in_1_1(x1)  =  if_goal_0_in_1_1(x1)
lte_2_in_ag2(x1, x2)  =  lte_2_in_ag1(x2)
if_lte_2_in_1_ag3(x1, x2, x3)  =  if_lte_2_in_1_ag1(x3)
lte_2_out_ag2(x1, x2)  =  lte_2_out_ag1(x1)
if_goal_0_in_2_2(x1, x2)  =  if_goal_0_in_2_1(x2)
even_1_in_g1(x1)  =  even_1_in_g1(x1)
if_even_1_in_1_g2(x1, x2)  =  if_even_1_in_1_g1(x2)
even_1_out_g1(x1)  =  even_1_out_g
goal_0_out_  =  goal_0_out_
EVEN_1_IN_G1(x1)  =  EVEN_1_IN_G1(x1)

We have to consider all (P,R,Pi)-chains
For (infinitary) constructor rewriting we can delete all non-usable rules from R.

↳ PROLOG
  ↳ PrologToPiTRSProof
    ↳ PiTRS
      ↳ DependencyPairsProof
        ↳ PiDP
          ↳ DependencyGraphProof
            ↳ AND
              ↳ PiDP
                ↳ UsableRulesProof
PiDP
                    ↳ PiDPToQDPProof
              ↳ PiDP

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

EVEN_1_IN_G1(s_11(s_11(X))) -> EVEN_1_IN_G1(X)

R is empty.
Pi is empty.
We have to consider all (P,R,Pi)-chains
Transforming (infinitary) constructor rewriting Pi-DP problem into ordinary QDP problem by application of Pi.

↳ PROLOG
  ↳ PrologToPiTRSProof
    ↳ PiTRS
      ↳ DependencyPairsProof
        ↳ PiDP
          ↳ DependencyGraphProof
            ↳ AND
              ↳ PiDP
                ↳ UsableRulesProof
                  ↳ PiDP
                    ↳ PiDPToQDPProof
QDP
                        ↳ QDPSizeChangeProof
              ↳ PiDP

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

EVEN_1_IN_G1(s_11(s_11(X))) -> EVEN_1_IN_G1(X)

R is empty.
Q is empty.
We have to consider all (P,Q,R)-chains.
The head symbols of this DP problem are {EVEN_1_IN_G1}.
By using the subterm criterion together with the size-change analysis we have proven that there are no infinite chains for this DP problem.

From the DPs we obtained the following set of size-change graphs:



↳ PROLOG
  ↳ PrologToPiTRSProof
    ↳ PiTRS
      ↳ DependencyPairsProof
        ↳ PiDP
          ↳ DependencyGraphProof
            ↳ AND
              ↳ PiDP
PiDP
                ↳ UsableRulesProof

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

LTE_2_IN_AG2(s_11(X), s_11(Y)) -> LTE_2_IN_AG2(X, Y)

The TRS R consists of the following rules:

goal_0_in_ -> if_goal_0_in_1_1(lte_2_in_ag2(X, s_11(s_11(s_11(s_11(0_0))))))
lte_2_in_ag2(s_11(X), s_11(Y)) -> if_lte_2_in_1_ag3(X, Y, lte_2_in_ag2(X, Y))
lte_2_in_ag2(0_0, Y) -> lte_2_out_ag2(0_0, Y)
if_lte_2_in_1_ag3(X, Y, lte_2_out_ag2(X, Y)) -> lte_2_out_ag2(s_11(X), s_11(Y))
if_goal_0_in_1_1(lte_2_out_ag2(X, s_11(s_11(s_11(s_11(0_0)))))) -> if_goal_0_in_2_2(X, even_1_in_g1(X))
even_1_in_g1(s_11(s_11(X))) -> if_even_1_in_1_g2(X, even_1_in_g1(X))
even_1_in_g1(0_0) -> even_1_out_g1(0_0)
if_even_1_in_1_g2(X, even_1_out_g1(X)) -> even_1_out_g1(s_11(s_11(X)))
if_goal_0_in_2_2(X, even_1_out_g1(X)) -> goal_0_out_

The argument filtering Pi contains the following mapping:
goal_0_in_  =  goal_0_in_
s_11(x1)  =  s_11(x1)
0_0  =  0_0
if_goal_0_in_1_1(x1)  =  if_goal_0_in_1_1(x1)
lte_2_in_ag2(x1, x2)  =  lte_2_in_ag1(x2)
if_lte_2_in_1_ag3(x1, x2, x3)  =  if_lte_2_in_1_ag1(x3)
lte_2_out_ag2(x1, x2)  =  lte_2_out_ag1(x1)
if_goal_0_in_2_2(x1, x2)  =  if_goal_0_in_2_1(x2)
even_1_in_g1(x1)  =  even_1_in_g1(x1)
if_even_1_in_1_g2(x1, x2)  =  if_even_1_in_1_g1(x2)
even_1_out_g1(x1)  =  even_1_out_g
goal_0_out_  =  goal_0_out_
LTE_2_IN_AG2(x1, x2)  =  LTE_2_IN_AG1(x2)

We have to consider all (P,R,Pi)-chains
For (infinitary) constructor rewriting we can delete all non-usable rules from R.

↳ PROLOG
  ↳ PrologToPiTRSProof
    ↳ PiTRS
      ↳ DependencyPairsProof
        ↳ PiDP
          ↳ DependencyGraphProof
            ↳ AND
              ↳ PiDP
              ↳ PiDP
                ↳ UsableRulesProof
PiDP
                    ↳ PiDPToQDPProof

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

LTE_2_IN_AG2(s_11(X), s_11(Y)) -> LTE_2_IN_AG2(X, Y)

R is empty.
The argument filtering Pi contains the following mapping:
s_11(x1)  =  s_11(x1)
LTE_2_IN_AG2(x1, x2)  =  LTE_2_IN_AG1(x2)

We have to consider all (P,R,Pi)-chains
Transforming (infinitary) constructor rewriting Pi-DP problem into ordinary QDP problem by application of Pi.

↳ PROLOG
  ↳ PrologToPiTRSProof
    ↳ PiTRS
      ↳ DependencyPairsProof
        ↳ PiDP
          ↳ DependencyGraphProof
            ↳ AND
              ↳ PiDP
              ↳ PiDP
                ↳ UsableRulesProof
                  ↳ PiDP
                    ↳ PiDPToQDPProof
QDP
                        ↳ QDPSizeChangeProof

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

LTE_2_IN_AG1(s_11(Y)) -> LTE_2_IN_AG1(Y)

R is empty.
Q is empty.
We have to consider all (P,Q,R)-chains.
The head symbols of this DP problem are {LTE_2_IN_AG1}.
By using the subterm criterion together with the size-change analysis we have proven that there are no infinite chains for this DP problem.

From the DPs we obtained the following set of size-change graphs: