Certification Problem

Input (COPS 934)

The rewrite relation of the following (conditional) TRS is considered.

h(x) a |
g(x) x |
g(x) a | h(x) ≈ b
c c |

The question is whether the following conditions are infeasible, i.e., there is no substitution σ such that all of the following is true:

Property / Task

Prove or disprove an infeasibility problem.

Answer / Result

Yes.

Proof (by nonreach @ CoCo 2023)

h(x) a |
g(x) x |
c c |

1 Infeasible Compound Conditions

We collect the conditions in the fresh compound-symbol |.

1.1 Non-reachability

We show non-reachability w.r.t. the underlying TRS.

1.1.1 Non-reachability by TCAP

Non-reachability is shown by the TCAP approximation.