Certification Problem

Input (TPDB TRS_Standard/Transformed_CSR_04/Ex6_GM04_GM)

The rewrite relation of the following TRS is considered.

a__c a__f(g(c)) (1)
a__f(g(X)) g(X) (2)
mark(c) a__c (3)
mark(f(X)) a__f(X) (4)
mark(g(X)) g(X) (5)
a__c c (6)
a__f(X) f(X) (7)

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(f) = 7 weight(f) = 0
prec(mark) = 5 weight(mark) = 6
prec(a__f) = 0 weight(a__f) = 1
prec(g) = 4 weight(g) = 1
prec(c) = 2 weight(c) = 4
prec(a__c) = 1 weight(a__c) = 6
all of the following rules can be deleted.
a__c a__f(g(c)) (1)
a__f(g(X)) g(X) (2)
mark(c) a__c (3)
mark(f(X)) a__f(X) (4)
mark(g(X)) g(X) (5)
a__c c (6)
a__f(X) f(X) (7)

1.1 R is empty

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