NO proof of Transformed_CSR_04_Ex14_Luc06_L.trs # AProVE Commit ID: c69e44bd14796315568835c1ffa2502984884775 jera 20211004 unpublished Termination w.r.t. Q of the given QTRS could be disproven: (0) QTRS (1) QTRS Reverse [EQUIVALENT, 0 ms] (2) QTRS (3) QTRSRRRProof [EQUIVALENT, 6 ms] (4) QTRS (5) Overlay + Local Confluence [EQUIVALENT, 0 ms] (6) QTRS (7) DependencyPairsProof [EQUIVALENT, 0 ms] (8) QDP (9) DependencyGraphProof [EQUIVALENT, 0 ms] (10) QDP (11) UsableRulesProof [EQUIVALENT, 0 ms] (12) QDP (13) QReductionProof [EQUIVALENT, 0 ms] (14) QDP (15) MNOCProof [EQUIVALENT, 0 ms] (16) QDP (17) NonTerminationLoopProof [COMPLETE, 0 ms] (18) NO ---------------------------------------- (0) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: h(X) -> g(X) g(a) -> f(b) f(X) -> h(a) a -> b Q is empty. ---------------------------------------- (1) QTRS Reverse (EQUIVALENT) We applied the QTRS Reverse Processor [REVERSE]. ---------------------------------------- (2) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: h(X) -> g(X) a'(g(x)) -> b'(f(x)) f(X) -> a'(h(X)) a'(x) -> b'(x) Q is empty. ---------------------------------------- (3) QTRSRRRProof (EQUIVALENT) Used ordering: Polynomial interpretation [POLO]: POL(a'(x_1)) = 1 + x_1 POL(b'(x_1)) = x_1 POL(f(x_1)) = 1 + x_1 POL(g(x_1)) = x_1 POL(h(x_1)) = x_1 With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly: a'(x) -> b'(x) ---------------------------------------- (4) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: h(X) -> g(X) a'(g(x)) -> b'(f(x)) f(X) -> a'(h(X)) Q is empty. ---------------------------------------- (5) Overlay + Local Confluence (EQUIVALENT) The TRS is overlay and locally confluent. By [NOC] we can switch to innermost. ---------------------------------------- (6) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: h(X) -> g(X) a'(g(x)) -> b'(f(x)) f(X) -> a'(h(X)) The set Q consists of the following terms: h(x0) a'(g(x0)) f(x0) ---------------------------------------- (7) DependencyPairsProof (EQUIVALENT) Using Dependency Pairs [AG00,LPAR04] we result in the following initial DP problem. ---------------------------------------- (8) Obligation: Q DP problem: The TRS P consists of the following rules: A'(g(x)) -> F(x) F(X) -> A'(h(X)) F(X) -> H(X) The TRS R consists of the following rules: h(X) -> g(X) a'(g(x)) -> b'(f(x)) f(X) -> a'(h(X)) The set Q consists of the following terms: h(x0) a'(g(x0)) f(x0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (9) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node. ---------------------------------------- (10) Obligation: Q DP problem: The TRS P consists of the following rules: F(X) -> A'(h(X)) A'(g(x)) -> F(x) The TRS R consists of the following rules: h(X) -> g(X) a'(g(x)) -> b'(f(x)) f(X) -> a'(h(X)) The set Q consists of the following terms: h(x0) a'(g(x0)) f(x0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (11) UsableRulesProof (EQUIVALENT) As all Q-normal forms are R-normal forms we are in the innermost case. Hence, by the usable rules processor [LPAR04] we can delete all non-usable rules [FROCOS05] from R. ---------------------------------------- (12) Obligation: Q DP problem: The TRS P consists of the following rules: F(X) -> A'(h(X)) A'(g(x)) -> F(x) The TRS R consists of the following rules: h(X) -> g(X) The set Q consists of the following terms: h(x0) a'(g(x0)) f(x0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (13) QReductionProof (EQUIVALENT) We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.[THIEMANN]. a'(g(x0)) f(x0) ---------------------------------------- (14) Obligation: Q DP problem: The TRS P consists of the following rules: F(X) -> A'(h(X)) A'(g(x)) -> F(x) The TRS R consists of the following rules: h(X) -> g(X) The set Q consists of the following terms: h(x0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (15) MNOCProof (EQUIVALENT) We use the modular non-overlap check [FROCOS05] to decrease Q to the empty set. ---------------------------------------- (16) Obligation: Q DP problem: The TRS P consists of the following rules: F(X) -> A'(h(X)) A'(g(x)) -> F(x) The TRS R consists of the following rules: h(X) -> g(X) Q is empty. We have to consider all (P,Q,R)-chains. ---------------------------------------- (17) NonTerminationLoopProof (COMPLETE) We used the non-termination processor [FROCOS05] to show that the DP problem is infinite. Found a loop by narrowing to the left: s = A'(h(X)) evaluates to t =A'(h(X)) Thus s starts an infinite chain as s semiunifies with t with the following substitutions: * Matcher: [ ] * Semiunifier: [ ] -------------------------------------------------------------------------------- Rewriting sequence A'(h(X)) -> A'(g(X)) with rule h(X') -> g(X') at position [0] and matcher [X' / X] A'(g(X)) -> F(X) with rule A'(g(x)) -> F(x) at position [] and matcher [x / X] F(X) -> A'(h(X)) with rule F(X) -> A'(h(X)) Now applying the matcher to the start term leads to a term which is equal to the last term in the rewriting sequence All these steps are and every following step will be a correct step w.r.t to Q. ---------------------------------------- (18) NO