Problem: h(h(c(),a()),b()) -> b() a() -> h(a(),b()) a() -> a() Proof: Nonconfluence Processor: terms: h(h(c(),h(a(),b())),b()) *<- h(h(c(),a()),b()) ->* b() Qed first automaton: final states: {11} transitions: b() -> 13,12 c() -> 16* a() -> 14* h(16,15) -> 17* h(14,13) -> 15* h(17,12) -> 11* h(14,12) -> 14* second automaton: final states: {10} transitions: b() -> 10*