Certification Problem

Input (TPDB TRS_Standard/Rubio_04/koen)

The rewrite relation of the following TRS is considered.

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

Property / Task

Prove or disprove termination.

Answer / Result

Yes.

Proof (by AProVE @ termCOMP 2023)

1 Rule Removal

Using the Knuth Bendix order with w0 = 1 and the following precedence and weight functions
prec(s) = 0 weight(s) = 1
prec(a) = 1 weight(a) = 1
prec(c) = 2 weight(c) = 2
prec(f) = 3 weight(f) = 1
all of the following rules can be deleted.
f(s(X),X) f(X,a(X)) (1)
f(X,c(X)) f(s(X),X) (2)
f(X,X) c(X) (3)

1.1 R is empty

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