Certification Problem

Input (TPDB SRS_Standard/Trafo_06/dup06)

The rewrite relation of the following TRS is considered.

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

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(c(c(x1)))) b#(b(b(x1))) (4)
b#(b(a(a(x1)))) a#(c(c(b(b(x1))))) (5)
a#(a(b(b(x1)))) b#(b(c(c(a(a(x1)))))) (6)
a#(a(b(b(x1)))) a#(a(x1)) (7)
a#(a(b(b(x1)))) a#(x1) (8)
b#(b(a(a(x1)))) b#(b(x1)) (9)
a#(a(b(b(x1)))) b#(c(c(a(a(x1))))) (10)
b#(b(a(a(x1)))) a#(a(c(c(b(b(x1)))))) (11)
b#(b(c(c(x1)))) b#(b(x1)) (12)
b#(b(c(c(x1)))) b#(b(b(b(x1)))) (13)
b#(b(a(a(x1)))) b#(x1) (14)
b#(b(c(c(x1)))) b#(x1) (15)

1.1 Dependency Graph Processor

The dependency pairs are split into 2 components.