NO (ignored inputs)COMMENT reduction failed Rewrite Rules: [ c -> c, a -> f(h(h(f(a),f(f(c))),b)), c -> a, h(c,f(b)) -> c ] Apply Direct Methods... Inner CPs: [ h(c,f(b)) = c, h(a,f(b)) = c ] Outer CPs: [ c = a ] not Overlay, check Termination... unknown/not Terminating unknown Knuth & Bendix Linear unknown Development Closed unknown Strongly Closed unknown Weakly-Non-Overlapping & Non-Collapsing & Shallow inner CP cond (upside-parallel) innter CP Cond (outside) unknown Upside-Parallel-Closed/Outside-Closed (inner) Parallel CPs: (not computed) unknown Toyama (Parallel CPs) Simultaneous CPs: [ a = c, c = h(c,f(b)), c = a, c = h(a,f(b)), h(c,f(b)) = c, h(a,f(b)) = c ] unknown Okui (Simultaneous CPs) unknown Strongly Depth-Preserving & Root-E-Closed/Non-E-Overlapping unknown Strongly Weight-Preserving & Root-E-Closed/Non-E-Overlapping check Locally Decreasing Diagrams by Rule Labelling... Critical Pair by Rules <0, 3> preceded by [(h,1)] joinable by a reduction of rules <[([],3)], []> Critical Pair by Rules <2, 3> preceded by [(h,1)] unknown Diagram Decreasing check Non-Confluence... obtain 10 rules by 3 steps unfolding obtain 100 candidates for checking non-joinability check by TCAP-Approximation (success) (success) (success) (success) (success) (success) (success) (success) (failure) check by Ordering(rpo), check by Tree-Automata Approximation (success) where F = {(a,0),(b,0),(c,0),(f,1),(h,2)} Q = {q_0,q_1,q_{a},q_{b},q_{c},q_{f(a)},q_{f(b)},q_{f(c)},q_{f(f(c))},q_{h(h(f(a),f(f(c))),b)},q_{h(f(a),f(f(c)))}} Qf = {q_0,q_1} Delta = [ a -> q_1, a -> q_{a}, a -> q_{c}, b -> q_{b}, c -> q_{c}, f(q_{a}) -> q_{f(a)}, f(q_{b}) -> q_{f(b)}, f(q_{c}) -> q_{f(c)}, f(q_{f(c)}) -> q_{f(f(c))}, f(q_{h(h(f(a),f(f(c))),b)}) -> q_1, f(q_{h(h(f(a),f(f(c))),b)}) -> q_{a}, f(q_{h(h(f(a),f(f(c))),b)}) -> q_{c}, h(q_{a},q_{f(b)}) -> q_0, h(q_{f(a)},q_{f(f(c))}) -> q_{h(f(a),f(f(c)))}, h(q_{h(f(a),f(f(c)))},q_{b}) -> q_{h(h(f(a),f(f(c))),b)} ] (failure) check by Interpretation(mod2) (success) Polynomial Interpretation: a:= (1) b:= 0 c:= (1) f:= (1) h:= 0 [a]-[f(h(h(f(a),f(f(c))),b))] = 0 = 0 (mod 2) [c]-[c] = 0 = 0 (mod 2) [c]-[a] = 0 = 0 (mod 2) [f(h(h(f(a),f(f(c))),b))]-[a] = 0 = 0 (mod 2) [c]-[c] = 0 = 0 (mod 2) [a]-[c] = 0 = 0 (mod 2) [h(f(h(h(f(a),f(f(a))),b)),f(b))]-[a] = (~1) = 1 (mod 2) (success) Witness for Non-Confluence: a> Direct Methods: not CR Combined result: not CR /tmp/filet8vRJV.trs: Success(not CR) (141 msec.)