YES Problem: strict: n(s(x1)) -> s(x1) o(s(x1)) -> s(x1) weak: t(x1) -> t(c(n(x1))) c(n(x1)) -> n(c(x1)) c(o(x1)) -> o(c(x1)) c(o(x1)) -> o(x1) Proof: Arctic Interpretation Processor: dimension: 1 interpretation: [c](x0) = x0, [n](x0) = x0, [t](x0) = 1x0, [s](x0) = x0, [o](x0) = 7x0 orientation: n(s(x1)) = x1 >= x1 = s(x1) o(s(x1)) = 7x1 >= x1 = s(x1) t(x1) = 1x1 >= 1x1 = t(c(n(x1))) c(n(x1)) = x1 >= x1 = n(c(x1)) c(o(x1)) = 7x1 >= 7x1 = o(c(x1)) c(o(x1)) = 7x1 >= 7x1 = o(x1) problem: strict: n(s(x1)) -> s(x1) weak: t(x1) -> t(c(n(x1))) c(n(x1)) -> n(c(x1)) c(o(x1)) -> o(c(x1)) c(o(x1)) -> o(x1) Matrix Interpretation Processor: dim=2 interpretation: [1 0] [c](x0) = [0 0]x0, [1 1] [n](x0) = [0 1]x0, [2 2] [t](x0) = [1 1]x0, [1 1] [0] [s](x0) = [2 0]x0 + [2], [2 2] [o](x0) = [0 0]x0 orientation: [3 1] [2] [1 1] [0] n(s(x1)) = [2 0]x1 + [2] >= [2 0]x1 + [2] = s(x1) [2 2] [2 2] t(x1) = [1 1]x1 >= [1 1]x1 = t(c(n(x1))) [1 1] [1 0] c(n(x1)) = [0 0]x1 >= [0 0]x1 = n(c(x1)) [2 2] [2 0] c(o(x1)) = [0 0]x1 >= [0 0]x1 = o(c(x1)) [2 2] [2 2] c(o(x1)) = [0 0]x1 >= [0 0]x1 = o(x1) problem: strict: weak: t(x1) -> t(c(n(x1))) c(n(x1)) -> n(c(x1)) c(o(x1)) -> o(c(x1)) c(o(x1)) -> o(x1) Qed