Certification Problem

Input (TPDB TRS_Standard/SK90/2.56)

The rewrite relation of the following TRS is considered.

f(a,x) g(a,x) (1)
g(a,x) f(b,x) (2)
f(a,x) f(b,x) (3)

Property / Task

Prove or disprove termination.

Answer / Result

Yes.

Proof (by ttt2 @ termCOMP 2023)

1 Rule Removal

Using the Knuth Bendix order with w0 = 1 and the following precedence and weight functions
prec(b) = 2 weight(b) = 1
prec(g) = 1 weight(g) = 0
prec(f) = 0 weight(f) = 4
prec(a) = 3 weight(a) = 6
all of the following rules can be deleted.
f(a,x) g(a,x) (1)
g(a,x) f(b,x) (2)
f(a,x) f(b,x) (3)

1.1 R is empty

There are no rules in the TRS. Hence, it is terminating.