Certification Problem

Input (TPDB SRS_Standard/Waldmann_07_size12/size-12-alpha-3-num-497)

The rewrite relation of the following TRS is considered.

a(a(x1)) b(a(b(c(c(x1))))) (1)
c(a(x1)) x1 (2)
c(b(x1)) a(x1) (3)

Property / Task

Prove or disprove termination.

Answer / Result

No.

Proof (by AProVE @ termCOMP 2023)

1 Looping derivation

There is a looping derivation.

a a b a b a b a a b+ b a b b a b a a b a b a b a a b c c

The derivation can be derived as follows.