YES Problem: average(s(x),y) -> average(x,s(y)) average(x,s(s(s(y)))) -> s(average(s(x),y)) average(0(),0()) -> 0() average(0(),s(0())) -> 0() average(0(),s(s(0()))) -> s(0()) Proof: Matrix Interpretation Processor: dim=3 interpretation: [0] [0] = [0] [0], [1 0 0] [1 0 0] [1] [average](x0, x1) = [0 0 0]x0 + [0 1 0]x1 + [1] [1 0 0] [0 1 0] [0], [1 0 0] [s](x0) = [0 0 0]x0 [0 0 0] orientation: [1 0 0] [1 0 0] [1] [1 0 0] [1 0 0] [1] average(s(x),y) = [0 0 0]x + [0 1 0]y + [1] >= [0 0 0]x + [0 0 0]y + [1] = average(x,s(y)) [1 0 0] [0 1 0] [0] [1 0 0] [0 0 0] [0] [1 0 0] [1 0 0] [1] [1 0 0] [1 0 0] [1] average(x,s(s(s(y)))) = [0 0 0]x + [0 0 0]y + [1] >= [0 0 0]x + [0 0 0]y + [0] = s(average(s(x),y)) [1 0 0] [0 0 0] [0] [0 0 0] [0 0 0] [0] [1] [0] average(0(),0()) = [1] >= [0] = 0() [0] [0] [1] [0] average(0(),s(0())) = [1] >= [0] = 0() [0] [0] [1] [0] average(0(),s(s(0()))) = [1] >= [0] = s(0()) [0] [0] problem: average(s(x),y) -> average(x,s(y)) average(x,s(s(s(y)))) -> s(average(s(x),y)) Matrix Interpretation Processor: dim=1 interpretation: [average](x0, x1) = x0 + x1, [s](x0) = x0 + 5 orientation: average(s(x),y) = x + y + 5 >= x + y + 5 = average(x,s(y)) average(x,s(s(s(y)))) = x + y + 15 >= x + y + 10 = s(average(s(x),y)) problem: average(s(x),y) -> average(x,s(y)) Matrix Interpretation Processor: dim=3 interpretation: [1 0 1] [1 0 0] [average](x0, x1) = [0 0 0]x0 + [0 0 0]x1 [0 0 0] [0 0 0] , [1 0 0] [0] [s](x0) = [0 0 0]x0 + [0] [0 0 1] [1] orientation: [1 0 1] [1 0 0] [1] [1 0 1] [1 0 0] average(s(x),y) = [0 0 0]x + [0 0 0]y + [0] >= [0 0 0]x + [0 0 0]y = average(x,s(y)) [0 0 0] [0 0 0] [0] [0 0 0] [0 0 0] problem: Qed