YES Problem: a(a(b(b(x1)))) -> b(b(b(a(a(a(x1)))))) Proof: Bounds Processor: bound: 3 enrichment: match automaton: final states: {1} transitions: b1(34) -> 35* b1(11) -> 12* b1(32) -> 33* b1(12) -> 13* b1(33) -> 34* b1(13) -> 14* b2(41) -> 42* b2(60) -> 61* b2(40) -> 41* b2(39) -> 40* b2(62) -> 63* b2(61) -> 62* a1(30) -> 31* a1(31) -> 32* a1(10) -> 11* a1(29) -> 30* a1(8) -> 9* a1(9) -> 10* f20() -> 2* a0(3) -> 4* a0(4) -> 5* a0(2) -> 3* b0(5) -> 6* b0(6) -> 7* b0(7) -> 1* a2(57) -> 58* a2(36) -> 37* a2(38) -> 39* a2(58) -> 59* a2(37) -> 38* a2(59) -> 60* a3(65) -> 66* a3(66) -> 67* a3(64) -> 65* b3(69) -> 70* b3(68) -> 69* b3(67) -> 68* 70 -> 39* 35 -> 10* 42 -> 31* 63 -> 37* 14 -> 5* 11 -> 36* 6 -> 8* 13 -> 29* 1 -> 3,4 61 -> 64* 33 -> 57* problem: Qed