YES(?,O(n^1)) Problem: a(b(x1)) -> b(c(a(x1))) b(c(x1)) -> c(b(b(x1))) c(a(x1)) -> a(c(x1)) Proof: Bounds Processor: bound: 0 enrichment: match automaton: final states: {4,3,2} transitions: a0(1) -> 2* b0(1) -> 3* c0(1) -> 4* f60() -> 1* problem: Qed