YES Problem: half(0()) -> 0() half(s(s(x))) -> s(half(x)) log(s(0())) -> 0() log(s(s(x))) -> s(log(s(half(x)))) Proof: Matrix Interpretation Processor: dim=3 interpretation: [1 0 0] [1] [log](x0) = [0 0 1]x0 + [0] [1 0 0] [1], [1 0 0] [s](x0) = [0 0 0]x0 [1 0 0] , [1 0 0] [0] [half](x0) = [0 0 0]x0 + [1] [1 0 0] [1], [0] [0] = [0] [0] orientation: [0] [0] half(0()) = [1] >= [0] = 0() [1] [0] [1 0 0] [0] [1 0 0] half(s(s(x))) = [0 0 0]x + [1] >= [0 0 0]x = s(half(x)) [1 0 0] [1] [1 0 0] [1] [0] log(s(0())) = [0] >= [0] = 0() [1] [0] [1 0 0] [1] [1 0 0] [1] log(s(s(x))) = [1 0 0]x + [0] >= [0 0 0]x + [0] = s(log(s(half(x)))) [1 0 0] [1] [1 0 0] [1] problem: half(0()) -> 0() half(s(s(x))) -> s(half(x)) log(s(s(x))) -> s(log(s(half(x)))) Matrix Interpretation Processor: dim=1 interpretation: [log](x0) = x0, [s](x0) = 2x0 + 6, [half](x0) = x0, [0] = 1 orientation: half(0()) = 1 >= 1 = 0() half(s(s(x))) = 4x + 18 >= 2x + 6 = s(half(x)) log(s(s(x))) = 4x + 18 >= 4x + 18 = s(log(s(half(x)))) problem: half(0()) -> 0() log(s(s(x))) -> s(log(s(half(x)))) Matrix Interpretation Processor: dim=3 interpretation: [1 0 1] [log](x0) = [1 0 1]x0 [1 0 1] , [1 0 0] [0] [s](x0) = [0 0 1]x0 + [1] [0 1 0] [0], [1 0 1] [half](x0) = [0 0 0]x0 [0 1 1] , [0] [0] = [0] [1] orientation: [1] [0] half(0()) = [0] >= [0] = 0() [1] [1] [1 0 1] [1] [1 0 1] [0] log(s(s(x))) = [1 0 1]x + [1] >= [1 0 1]x + [1] = s(log(s(half(x)))) [1 0 1] [1] [1 0 1] [0] problem: Qed