YES Problem: a(a(a(b(b(b(x1)))))) -> b(b(b(b(a(a(a(a(x1)))))))) Proof: String Reversal Processor: b(b(b(a(a(a(x1)))))) -> a(a(a(a(b(b(b(b(x1)))))))) Bounds Processor: bound: 5 enrichment: match automaton: final states: {2,1} transitions: b3(167) -> 168* b3(157) -> 158* b3(169) -> 170* b3(159) -> 160* b3(149) -> 150* b3(119) -> 120* b3(166) -> 167* b3(151) -> 152* b3(121) -> 122* b3(168) -> 169* b3(158) -> 159* b3(148) -> 149* b3(118) -> 119* b3(160) -> 161* b3(150) -> 151* b3(135) -> 136* b3(120) -> 121* a4(192) -> 193* a4(182) -> 183* a4(179) -> 180* a4(191) -> 192* a4(181) -> 182* a4(193) -> 194* a4(190) -> 191* a4(180) -> 181* b4(187) -> 188* b4(177) -> 178* b4(189) -> 190* b4(186) -> 187* b4(176) -> 177* b4(188) -> 189* b4(178) -> 179* b4(175) -> 176* b0(2) -> 1* b0(1) -> 1* a5(202) -> 203* a5(199) -> 200* a5(201) -> 202* a5(200) -> 201* a0(2) -> 2* a0(1) -> 2* b5(197) -> 198* b5(196) -> 197* b5(198) -> 199* b5(195) -> 196* a1(40) -> 41* a1(10) -> 11* a1(37) -> 38* a1(39) -> 40* a1(9) -> 10* a1(11) -> 12* a1(38) -> 39* a1(8) -> 9* b1(35) -> 36* b1(5) -> 6* b1(7) -> 8* b1(79) -> 80* b1(34) -> 35* b1(4) -> 5* b1(81) -> 82* b1(46) -> 47* b1(36) -> 37* b1(31) -> 32* b1(6) -> 7* b1(48) -> 49* b1(33) -> 34* b1(85) -> 86* a2(55) -> 56* a2(142) -> 143* a2(97) -> 98* a2(57) -> 58* a2(144) -> 145* a2(114) -> 115* a2(54) -> 55* a2(141) -> 142* a2(116) -> 117* a2(96) -> 97* a2(56) -> 57* a2(143) -> 144* a2(113) -> 114* a2(98) -> 99* a2(115) -> 116* a2(95) -> 96* b2(50) -> 51* b2(137) -> 138* b2(127) -> 128* b2(112) -> 113* b2(92) -> 93* b2(87) -> 88* b2(52) -> 53* b2(139) -> 140* b2(129) -> 130* b2(109) -> 110* b2(94) -> 95* b2(146) -> 147* b2(111) -> 112* b2(91) -> 92* b2(51) -> 52* b2(138) -> 139* b2(93) -> 94* b2(53) -> 54* b2(140) -> 141* b2(110) -> 111* a3(172) -> 173* a3(162) -> 163* a3(152) -> 153* a3(122) -> 123* a3(164) -> 165* a3(154) -> 155* a3(124) -> 125* a3(171) -> 172* a3(161) -> 162* a3(173) -> 174* a3(163) -> 164* a3(153) -> 154* a3(123) -> 124* a3(170) -> 171* a3(155) -> 156* a3(125) -> 126* 1 -> 31* 2 -> 4* 8 -> 91* 9 -> 50,48 10 -> 46* 11 -> 33* 12 -> 6,7,32,1 32 -> 5* 37 -> 127* 38 -> 87,85 39 -> 81* 40 -> 79* 41 -> 6,1,31,7,32 47 -> 34* 49 -> 34* 54 -> 135* 55 -> 118* 56 -> 109* 57 -> 129* 58 -> 93,92,8,7 80 -> 5* 82 -> 5* 86 -> 5* 88 -> 51* 96 -> 146* 99 -> 36* 114 -> 166,137 117 -> 36,53 124 -> 157* 126 -> 95,93,94 128 -> 51* 130 -> 92* 136 -> 119* 142 -> 148* 145 -> 52* 147 -> 138* 153 -> 175* 156 -> 136* 165 -> 140* 174 -> 120* 179 -> 195* 182 -> 186* 183 -> 122* 194 -> 160* 203 -> 189* problem: Qed