Certification Problem

Input (TPDB SRS_Standard/Waldmann_07_size12/size-12-alpha-3-num-473)

The rewrite relation of the following TRS is considered.

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

Property / Task

Prove or disprove termination.

Answer / Result

Yes.

Proof (by AProVE @ termCOMP 2023)

1 Dependency Pair Transformation

The following set of initial dependency pairs has been identified.
a#(a(x1)) a#(b(x1)) (4)
a#(a(x1)) b#(x1) (5)
a#(c(x1)) b#(x1) (6)
b#(b(x1)) b#(a(x1)) (7)
b#(b(x1)) a#(x1) (8)

1.1 Reduction Pair Processor

Using the linear polynomial interpretation over the naturals
[a#(x1)] = 1 + 1 · x1
[a(x1)] = 1 + 1 · x1
[b(x1)] = 1 + 1 · x1
[b#(x1)] = 1 + 1 · x1
[c(x1)] = 1 · x1
the pairs
a#(a(x1)) b#(x1) (5)
b#(b(x1)) a#(x1) (8)
could be deleted.

1.1.1 Dependency Graph Processor

The dependency pairs are split into 2 components.