Certification Problem

Input (TPDB SRS_Standard/Zantema_04/z122)

The rewrite relation of the following TRS is considered.

a(a(x1)) b(c(x1)) (1)
b(b(x1)) c(d(x1)) (2)
c(c(x1)) d(d(d(x1))) (3)
d(c(x1)) b(f(x1)) (4)
d(d(d(x1))) a(c(x1)) (5)
f(f(x1)) f(b(x1)) (6)

Property / Task

Prove or disprove termination.

Answer / Result

Yes.

Proof (by NaTT @ termCOMP 2023)

1 Dependency Pair Transformation

The following set of initial dependency pairs has been identified.
b#(b(x1)) d#(x1) (7)
d#(d(d(x1))) c#(x1) (8)
d#(c(x1)) f#(x1) (9)
c#(c(x1)) d#(x1) (10)
a#(a(x1)) c#(x1) (11)
d#(c(x1)) b#(f(x1)) (12)
c#(c(x1)) d#(d(d(x1))) (13)
a#(a(x1)) b#(c(x1)) (14)
d#(d(d(x1))) a#(c(x1)) (15)
f#(f(x1)) f#(b(x1)) (16)
b#(b(x1)) c#(d(x1)) (17)
c#(c(x1)) d#(d(x1)) (18)
f#(f(x1)) b#(x1) (19)

1.1 Dependency Graph Processor

The dependency pairs are split into 1 component.