Problem: minus(minus(x)) -> x minus(h(x)) -> h(minus(x)) minus(f(x,y)) -> f(minus(y),minus(x)) Proof: Bounds Processor: bound: 1 enrichment: match automaton: final states: {3} transitions: f1(4,4) -> 4,3 minus1(2) -> 4* minus1(1) -> 4* h1(4) -> 4,3 minus0(2) -> 3* minus0(1) -> 3* h0(2) -> 1* h0(1) -> 1* f0(1,2) -> 2* f0(2,1) -> 2* f0(1,1) -> 2* f0(2,2) -> 2* problem: Qed