NO Problem: sq(0(x)) -> p(s(p(s(p(p(p(p(s(s(s(s(0(p(s(p(s(x))))))))))))))))) sq(s(x)) -> s(p(s(p(s(p(p(s(s(twice(p(s(p(s(p(p(p(s(s(s(sq(p(p(p(p(p(p(s(s(s(s(s(s(x))))))))))))))))))))))))))))))))) twice(0(x)) -> p(p(p(p(s(s(p(s(s(s(0(p(p(p(s(s(s(p(p(s(s(p(s(p(s(p(s(x))))))))))))))))))))))))))) twice(s(x)) -> p(p(s(s(s(p(p(s(s(s(twice(p(s(p(s(x))))))))))))))) p(p(s(x))) -> p(x) p(s(x)) -> x p(0(x)) -> 0(s(s(s(s(s(s(s(s(s(s(s(x)))))))))))) 0(x) -> x Proof: Nonconfluence Processor: terms: p(f5()) *<- p(0(f5())) ->* 0(s(s(s(s(s(s(s(s(s(s(s(f5())))))))))))) Qed first automaton: final states: {1} transitions: p(2) -> 1* f5() -> 2* second automaton: final states: {3} transitions: 0(15) -> 3* s(7) -> 8* s(12) -> 13* s(6) -> 7* s(9) -> 10* s(11) -> 12* s(5) -> 6* s(4) -> 5* s(8) -> 9* s(10) -> 11* s(14) -> 15* s(13) -> 14* f5() -> 4* 15 -> 3*