YES(?,O(n^1)) Problem: b(a(b(b(a(b(a(x1))))))) -> a(b(a(a(b(b(a(b(b(a(x1)))))))))) Proof: Bounds Processor: bound: 2 enrichment: match automaton: final states: {2,1} transitions: a1(35) -> 36* a1(10) -> 11* a1(7) -> 8* a1(4) -> 5* a1(11) -> 12* a1(13) -> 14* b1(5) -> 6* b1(12) -> 13* b1(39) -> 40* b1(9) -> 10* b1(41) -> 42* b1(6) -> 7* b1(8) -> 9* a2(50) -> 51* a2(52) -> 53* a2(49) -> 50* a2(46) -> 47* a2(43) -> 44* b0(2) -> 1* b0(1) -> 1* b2(45) -> 46* b2(47) -> 48* b2(54) -> 55* b2(44) -> 45* b2(51) -> 52* b2(48) -> 49* a0(2) -> 2* a0(1) -> 2* 1 -> 35* 2 -> 4* 10 -> 39* 11 -> 43* 13 -> 41* 14 -> 6,9,1 36 -> 5* 40 -> 7* 42 -> 7* 52 -> 54* 53 -> 9* 55 -> 46* problem: Qed