Certification Problem

Input (TPDB TRS_Standard/Strategy_removed_CSR_05/Ex1_GM99)

The rewrite relation of the following TRS is considered.

f(a,b,X) f(X,X,X) (1)
c a (2)
c b (3)

Property / Task

Prove or disprove termination.

Answer / Result

No.

Proof (by ttt2 @ termCOMP 2023)

1 Loop

The following loop proves nontermination.

t0 = f(c,c,c)
f(c,b,c)
f(a,b,c)
f(c,c,c)
= t3
where t3 = t0