YES(?,O(n^1)) Problem: a(a(x1)) -> a(b(b(b(x1)))) b(a(x1)) -> b(b(c(x1))) a(b(b(c(x1)))) -> a(a(a(b(x1)))) Proof: Bounds Processor: bound: 0 enrichment: match automaton: final states: {3,2} transitions: a0(1) -> 2* b0(1) -> 3* c0(1) -> 1* problem: Qed