Certification Problem
Input (TPDB TRS_Outermost/Strategy_outermost_added_08/4.49)
The rewrite relation of the following TRS is considered.
|
f(x,y,f(z,u,v)) |
→ |
f(f(x,y,z),u,f(x,y,v)) |
(1) |
The evaluation strategy is outermostProperty / Task
Prove or disprove termination.Answer / Result
No.Proof (by AProVE @ termCOMP 2023)
1 Loop
The following loop proves nontermination.
| t0
|
= |
f(x,y,f(z,u,v)) |
|
→
|
f(f(x,y,z),u,f(x,y,v)) |
|
= |
t1
|
where t1 =
t0σ
and
σ =
{x/f(x,y,z), y/u, z/x, u/y, v/v}