/export/starexec/sandbox2/solver/bin/starexec_run_default /export/starexec/sandbox2/benchmark/theBenchmark.xml /export/starexec/sandbox2/output/output_files -------------------------------------------------------------------------------- NO ** BEGIN proof argument ** The following pattern rule was generated by the strategy presented in Sect. 3 of [Emmes, Enger, Giesl, IJCAR'12]: [iteration = 2] f(tt,s(s(_0))){_0->s(s(_0))}^n{_0->0} -> f(tt,s(s(s(s(_0))))){_0->s(s(_0))}^n{_0->0} We apply Theorem 8 of [Emmes, Enger, Giesl, IJCAR'12] on this rule with m = 1, b = 1, pi = epsilon, sigma' = {} and mu' = {}. Hence the term f(tt,s(s(0))), obtained from instantiating n with 0 in the left-hand side of the rule, starts an infinite derivation w.r.t. the analyzed TRS. ** END proof argument ** ** BEGIN proof description ** ## Searching for a generalized rewrite rule (a rule whose right-hand side contains a variable that does not occur in the left-hand side)... No generalized rewrite rule found! ## Applying the DP framework... ## 2 initial DP problems to solve. ## First, we try to decompose these problems into smaller problems. ## Round 1 [2 DP problems]: ## DP problem: Dependency pairs = [f^#(tt,_0) -> f^#(isDouble(_0),s(s(_0)))] TRS = {f(tt,_0) -> f(isDouble(_0),s(s(_0))), isDouble(s(s(_0))) -> isDouble(_0), isDouble(0) -> tt} ## Trying with homeomorphic embeddings... Failed! ## Trying with polynomial interpretations... Failed! ## Trying with lexicographic path orders... Failed! ## Trying with Knuth-Bendix orders... Failed! Don't know whether this DP problem is finite. ## DP problem: Dependency pairs = [isDouble^#(s(s(_0))) -> isDouble^#(_0)] TRS = {f(tt,_0) -> f(isDouble(_0),s(s(_0))), isDouble(s(s(_0))) -> isDouble(_0), isDouble(0) -> tt} ## Trying with homeomorphic embeddings... Success! This DP problem is finite. ## A DP problem could not be proved finite. ## Now, we try to prove that this problem is infinite. ## Trying to prove non-looping nontermination # Iteration 0: non-looping nontermination not proved, 1 unfolded rule generated. # Iteration 1: non-looping nontermination not proved, 5 unfolded rules generated. # Iteration 2: success, non-looping nontermination proved, 14 unfolded rules generated. Here is the successful unfolding. Let IR be the TRS under analysis. IR contains the dependency pair f^#(tt,_0) -> f^#(isDouble(_0),s(s(_0))). We apply (I) of [Emmes, Enger, Giesl, IJCAR'12] to this dependency pair. ==> P0 = f^#(tt,_0){}^n{} -> f^#(isDouble(_0),s(s(_0))){}^n{} is in U_IR^0. We apply (VI) of [Emmes, Enger, Giesl, IJCAR'12] to this pattern rule at position [0] using the pattern rule isDouble(s(s(_0))){_0->s(s(_0))}^n{_0->_1} -> isDouble(_1){_0->s(s(_0))}^n{_0->_1} obtained from IR. ==> P1 = f^#(tt,s(s(_0))){_0->s(s(_0))}^n{_0->_1} -> f^#(isDouble(_1),s(s(s(s(_0))))){_0->s(s(_0))}^n{_0->_1} is in U_IR^1. We apply (V) + (IX) of [Emmes, Enger, Giesl, IJCAR'12] to this pattern rule at position [0] using the rule isDouble(0) -> tt of IR. ==> P2 = f^#(tt,s(s(_0))){_0->s(s(_0))}^n{_0->0} -> f^#(tt,s(s(s(s(_0))))){_0->s(s(_0))}^n{_0->0} is in U_IR^2. This DP problem is infinite. Proof run on Linux version 3.10.0-1160.25.1.el7.x86_64 for amd64 using Java version 1.8.0_292 ** END proof description ** Total number of generated unfolded rules = 58