YES Problem: f(0(x1)) -> s(0(x1)) d(0(x1)) -> 0(x1) d(s(x1)) -> s(s(d(x1))) f(s(x1)) -> d(f(x1)) Proof: Arctic Interpretation Processor: dimension: 1 interpretation: [d](x0) = x0, [s](x0) = x0, [f](x0) = 8x0, [0](x0) = 2x0 orientation: f(0(x1)) = 10x1 >= 2x1 = s(0(x1)) d(0(x1)) = 2x1 >= 2x1 = 0(x1) d(s(x1)) = x1 >= x1 = s(s(d(x1))) f(s(x1)) = 8x1 >= 8x1 = d(f(x1)) problem: d(0(x1)) -> 0(x1) d(s(x1)) -> s(s(d(x1))) f(s(x1)) -> d(f(x1)) Arctic Interpretation Processor: dimension: 2 interpretation: [0 0 ] [d](x0) = [-& 1 ]x0, [0 -&] [s](x0) = [0 0 ]x0, [1 0 ] [f](x0) = [-& -&]x0, [0 -&] [0](x0) = [3 0 ]x0 orientation: [3 0] [0 -&] d(0(x1)) = [4 1]x1 >= [3 0 ]x1 = 0(x1) [0 0] [0 0] d(s(x1)) = [1 1]x1 >= [0 1]x1 = s(s(d(x1))) [1 0 ] [1 0 ] f(s(x1)) = [-& -&]x1 >= [-& -&]x1 = d(f(x1)) problem: d(s(x1)) -> s(s(d(x1))) f(s(x1)) -> d(f(x1)) Bounds Processor: bound: 0 enrichment: match automaton: final states: {5,1} transitions: f40() -> 2* s0(4) -> 1* s0(3) -> 4* d0(2) -> 3* d0(6) -> 5* f0(2) -> 6* 1 -> 3* 5 -> 6* problem: Qed