Certification Problem
Input (TPDB TRS_Standard/Transformed_CSR_04/Ex6_GM04_FR)
The rewrite relation of the following TRS is considered.
| c |
→ |
f(n__g(n__c)) |
(1) |
|
f(n__g(X)) |
→ |
g(activate(X)) |
(2) |
|
g(X) |
→ |
n__g(X) |
(3) |
| c |
→ |
n__c |
(4) |
|
activate(n__g(X)) |
→ |
g(X) |
(5) |
|
activate(n__c) |
→ |
c |
(6) |
|
activate(X) |
→ |
X |
(7) |
Property / Task
Prove or disprove termination.Answer / Result
No.Proof (by ttt2 @ termCOMP 2023)
1 Loop
The following loop proves nontermination.
| t0
|
= |
c |
|
→
|
f(n__g(n__c)) |
|
→
|
g(activate(n__c)) |
|
→
|
g(c) |
|
= |
t3
|
where t3 =
C[t0]
and
C = g(☐)