/export/starexec/sandbox/solver/bin/starexec_run_default /export/starexec/sandbox/benchmark/theBenchmark.xml /export/starexec/sandbox/output/output_files -------------------------------------------------------------------------------- NO ** BEGIN proof argument ** The following rule was generated while unfolding the analyzed TRS: [iteration = 2] a(b(b(_0))) -> a(b(b(a(a(_0))))) Let l be the left-hand side and r be the right-hand side of this rule. Let p = epsilon, theta1 = {} and theta2 = {_0->a(a(_0))}. We have r|p = a(b(b(a(a(_0))))) and theta2(theta1(l)) = theta1(r|p). Hence, the term theta1(l) = a(b(b(_0))) loops 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... ## 1 initial DP problem to solve. ## First, we try to decompose this problem into smaller problems. ## Round 1 [1 DP problem]: ## DP problem: Dependency pairs = [a^#(b(_0)) -> a^#(a(_0)), a^#(b(_0)) -> a^#(_0)] TRS = {a(b(_0)) -> b(b(a(a(_0))))} ## 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. ## A DP problem could not be proved finite. ## Now, we try to prove that this problem is infinite. ## Trying to find a loop (forward=true, backward=false, max=-1) # max_depth=4, unfold_variables=false: # Iteration 0: no loop found, 2 unfolded rules generated. # Iteration 1: no loop found, 4 unfolded rules generated. # Iteration 2: success, found a loop, 1 unfolded rule generated. Here is the successful unfolding. Let IR be the TRS under analysis. L0 = a^#(b(_0)) -> a^#(a(_0)) [trans] is in U_IR^0. D = a^#(b(_0)) -> a^#(_0) is a dependency pair of IR. We build a composed triple from L0 and D. ==> L1 = [a^#(b(_0)) -> a^#(a(_0)), a^#(b(_1)) -> a^#(_1)] [comp] is in U_IR^1. Let p1 = [0]. We unfold the first rule of L1 forwards at position p1 with the rule a(b(_0)) -> b(b(a(a(_0)))). ==> L2 = [a^#(b(b(_0))) -> a^#(b(b(a(a(_0))))), a^#(b(_1)) -> a^#(_1)] [comp] 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 = 22