Certification Problem
Input (TPDB SRS_Standard/Mixed_SRS/touzet)
The rewrite relation of the following TRS is considered.
a(b(x1)) |
→ |
b(b(b(x1))) |
(1) |
b(a(x1)) |
→ |
a(a(a(x1))) |
(2) |
a(x1) |
→ |
x1 |
(3) |
b(x1) |
→ |
x1 |
(4) |
Property / Task
Prove or disprove termination.Answer / Result
Yes.Proof (by ttt2 @ termCOMP 2023)
1 Dependency Pair Transformation
The following set of initial dependency pairs has been identified.
a#(b(x1)) |
→ |
b#(b(x1)) |
(5) |
a#(b(x1)) |
→ |
b#(b(b(x1))) |
(6) |
b#(a(x1)) |
→ |
a#(a(x1)) |
(7) |
b#(a(x1)) |
→ |
a#(a(a(x1))) |
(8) |
1.1 Reduction Pair Processor with Usable Rules
Using the linear polynomial interpretation over (2 x 2)-matrices with strict dimension 1
over the arctic semiring over the integers
[a(x1)] |
= |
· x1 +
|
[b#(x1)] |
= |
· x1 +
|
[b(x1)] |
= |
· x1 +
|
[a#(x1)] |
= |
· x1 +
|
together with the usable
rules
a(b(x1)) |
→ |
b(b(b(x1))) |
(1) |
b(a(x1)) |
→ |
a(a(a(x1))) |
(2) |
a(x1) |
→ |
x1 |
(3) |
b(x1) |
→ |
x1 |
(4) |
(w.r.t. the implicit argument filter of the reduction pair),
the
pairs
a#(b(x1)) |
→ |
b#(b(x1)) |
(5) |
a#(b(x1)) |
→ |
b#(b(b(x1))) |
(6) |
could be deleted.
1.1.1 Dependency Graph Processor
The dependency pairs are split into 0
components.