Certification Problem
Input (TPDB SRS_Standard/Waldmann_07_size12/size-12-alpha-3-num-439)
The rewrite relation of the following TRS is considered.
a(x1) |
→ |
b(c(x1)) |
(1) |
a(a(x1)) |
→ |
x1 |
(2) |
a(b(b(x1))) |
→ |
b(b(a(a(x1)))) |
(3) |
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(b(x1))) |
→ |
a#(x1) |
(4) |
a#(b(b(x1))) |
→ |
a#(a(x1)) |
(5) |
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
[c(x1)] |
= |
· x1 +
|
[a#(x1)] |
= |
· x1 +
|
[a(x1)] |
= |
· x1 +
|
[b(x1)] |
= |
· x1 +
|
together with the usable
rules
a(x1) |
→ |
b(c(x1)) |
(1) |
a(a(x1)) |
→ |
x1 |
(2) |
a(b(b(x1))) |
→ |
b(b(a(a(x1)))) |
(3) |
(w.r.t. the implicit argument filter of the reduction pair),
the
pair
a#(b(b(x1))) |
→ |
a#(x1) |
(4) |
could be deleted.
1.1.1 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
[c(x1)] |
= |
· x1 +
|
[a#(x1)] |
= |
· x1 +
|
[a(x1)] |
= |
· x1 +
|
[b(x1)] |
= |
· x1 +
|
together with the usable
rules
a(x1) |
→ |
b(c(x1)) |
(1) |
a(a(x1)) |
→ |
x1 |
(2) |
a(b(b(x1))) |
→ |
b(b(a(a(x1)))) |
(3) |
(w.r.t. the implicit argument filter of the reduction pair),
the
pair
a#(b(b(x1))) |
→ |
a#(a(x1)) |
(5) |
could be deleted.
1.1.1.1 P is empty
There are no pairs anymore.