Termination w.r.t. Q of the following Term Rewriting System could be disproven:
Q restricted rewrite system:
The TRS R consists of the following rules:
f(X, g(X)) → f(1, g(X))
g(1) → g(0)
Q is empty.
↳ QTRS
↳ DependencyPairsProof
Q restricted rewrite system:
The TRS R consists of the following rules:
f(X, g(X)) → f(1, g(X))
g(1) → g(0)
Q is empty.
Using Dependency Pairs [1,15] we result in the following initial DP problem:
Q DP problem:
The TRS P consists of the following rules:
F(X, g(X)) → F(1, g(X))
G(1) → G(0)
The TRS R consists of the following rules:
f(X, g(X)) → f(1, g(X))
g(1) → g(0)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
↳ QTRS
↳ DependencyPairsProof
↳ QDP
↳ DependencyGraphProof
Q DP problem:
The TRS P consists of the following rules:
F(X, g(X)) → F(1, g(X))
G(1) → G(0)
The TRS R consists of the following rules:
f(X, g(X)) → f(1, g(X))
g(1) → g(0)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
The approximation of the Dependency Graph [15,17,22] contains 1 SCC with 1 less node.
↳ QTRS
↳ DependencyPairsProof
↳ QDP
↳ DependencyGraphProof
↳ QDP
↳ UsableRulesProof
Q DP problem:
The TRS P consists of the following rules:
F(X, g(X)) → F(1, g(X))
The TRS R consists of the following rules:
f(X, g(X)) → f(1, g(X))
g(1) → g(0)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
We can use the usable rules and reduction pair processor [15] with the Ce-compatible extension of the polynomial order that maps every function symbol to the sum of its argument. Then, we can delete all non-usable rules [17] from R.
↳ QTRS
↳ DependencyPairsProof
↳ QDP
↳ DependencyGraphProof
↳ QDP
↳ UsableRulesProof
↳ QDP
↳ Instantiation
Q DP problem:
The TRS P consists of the following rules:
F(X, g(X)) → F(1, g(X))
The TRS R consists of the following rules:
g(1) → g(0)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
By instantiating [15] the rule F(X, g(X)) → F(1, g(X)) we obtained the following new rules:
F(1, g(1)) → F(1, g(1))
↳ QTRS
↳ DependencyPairsProof
↳ QDP
↳ DependencyGraphProof
↳ QDP
↳ UsableRulesProof
↳ QDP
↳ Instantiation
↳ QDP
↳ RuleRemovalProof
Q DP problem:
The TRS P consists of the following rules:
F(1, g(1)) → F(1, g(1))
The TRS R consists of the following rules:
g(1) → g(0)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
By using the rule removal processor [15] with the following polynomial ordering [25], at least one Dependency Pair or term rewrite system rule of this QDP problem can be strictly oriented.
Strictly oriented rules of the TRS R:
g(1) → g(0)
Used ordering: POLO with Polynomial interpretation [25]:
POL(0) = 1
POL(1) = 2
POL(F(x1, x2)) = x1 + x2
POL(g(x1)) = 2·x1
↳ QTRS
↳ DependencyPairsProof
↳ QDP
↳ DependencyGraphProof
↳ QDP
↳ UsableRulesProof
↳ QDP
↳ Instantiation
↳ QDP
↳ RuleRemovalProof
↳ QDP
↳ NonTerminationProof
Q DP problem:
The TRS P consists of the following rules:
F(1, g(1)) → F(1, g(1))
R is empty.
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
We used the non-termination processor [17] to show that the DP problem is infinite.
Found a loop by semiunifying a rule from P directly.
The TRS P consists of the following rules:
F(1, g(1)) → F(1, g(1))
The TRS R consists of the following rules:none
s = F(1, g(1)) evaluates to t =F(1, g(1))
Thus s starts an infinite chain as s semiunifies with t with the following substitutions:
- Semiunifier: [ ]
- Matcher: [ ]
Rewriting sequence
The DP semiunifies directly so there is only one rewrite step from F(1, g(1)) to F(1, g(1)).