(0) Obligation:

Clauses:

f(X) :- g(s(s(s(X)))).
f(s(X)) :- f(X).
g(s(s(s(s(X))))) :- f(X).

Queries:

f(g).

(1) PrologToDTProblemTransformerProof (SOUND transformation)

Built DT problem from termination graph.

(2) Obligation:

Triples:

f1(s(T8)) :- f1(T8).
f1(s(T12)) :- f1(T12).

Clauses:

fc1(s(T8)) :- fc1(T8).
fc1(s(T12)) :- fc1(T12).

Afs:

f1(x1)  =  f1(x1)

(3) TriplesToPiDPProof (SOUND transformation)

We use the technique of [LOPSTR]. With regard to the inferred argument filtering the predicates were used in the following modes:
f1_in: (b)
Transforming TRIPLES into the following Term Rewriting System:
Pi DP problem:
The TRS P consists of the following rules:

F1_IN_G(s(T8)) → U1_G(T8, f1_in_g(T8))
F1_IN_G(s(T8)) → F1_IN_G(T8)
F1_IN_G(s(T12)) → U2_G(T12, f1_in_g(T12))

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

Infinitary Constructor Rewriting Termination of PiDP implies Termination of TRIPLES

(4) Obligation:

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

F1_IN_G(s(T8)) → U1_G(T8, f1_in_g(T8))
F1_IN_G(s(T8)) → F1_IN_G(T8)
F1_IN_G(s(T12)) → U2_G(T12, f1_in_g(T12))

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

(5) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LOPSTR] contains 1 SCC with 2 less nodes.

(6) Obligation:

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

F1_IN_G(s(T8)) → F1_IN_G(T8)

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

(7) PiDPToQDPProof (EQUIVALENT transformation)

Transforming (infinitary) constructor rewriting Pi-DP problem [LOPSTR] into ordinary QDP problem [LPAR04] by application of Pi.

(8) Obligation:

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

F1_IN_G(s(T8)) → F1_IN_G(T8)

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

(9) QDPSizeChangeProof (EQUIVALENT transformation)

By using the subterm criterion [SUBTERM_CRITERION] together with the size-change analysis [AAECC05] 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:

  • F1_IN_G(s(T8)) → F1_IN_G(T8)
    The graph contains the following edges 1 > 1

(10) YES