YES(?,O(n^1)) Problem: a(b(a(a(x1)))) -> c(b(a(b(a(x1))))) a(c(b(x1))) -> a(a(b(c(b(a(x1)))))) Proof: Bounds Processor: bound: 3 enrichment: match automaton: final states: {4} transitions: a3(92) -> 93* a3(93) -> 94* a3(88) -> 89* a1(20) -> 21* a1(49) -> 50* a1(19) -> 20* a1(11) -> 12* a1(13) -> 14* b3(89) -> 90* b3(91) -> 92* b1(45) -> 46* b1(12) -> 13* b1(14) -> 15* b1(43) -> 44* b1(18) -> 19* c3(90) -> 91* c1(15) -> 16* c1(17) -> 18* a2(57) -> 58* a2(84) -> 85* a2(79) -> 80* a2(64) -> 65* a2(26) -> 27* a2(83) -> 84* a2(73) -> 74* a2(58) -> 59* a2(53) -> 54* a2(28) -> 29* a0(4) -> 4* b2(102) -> 103* b2(82) -> 83* b2(62) -> 63* b2(27) -> 28* b2(54) -> 55* b2(29) -> 30* b2(56) -> 57* b2(80) -> 81* b0(4) -> 4* c2(55) -> 56* c2(30) -> 31* c2(81) -> 82* c0(4) -> 4* 4 -> 11* 13 -> 73,17 14 -> 53,49 16 -> 74,27,12,14,4 19 -> 64* 20 -> 43,26 21 -> 12,45,4 29 -> 88,79 31 -> 74,27,29,14 44 -> 13* 46 -> 13* 50 -> 12* 58 -> 62* 59 -> 54,50,12 63 -> 28* 65 -> 27* 74 -> 27* 84 -> 102* 85 -> 50* 94 -> 89,80,54 103 -> 28* problem: Qed