YES Problem: *(x,*(y,z)) -> *(*(x,y),z) *(x,x) -> x Proof: Matrix Interpretation Processor: dim=1 interpretation: [*](x0, x1) = x0 + 2x1 + 7 orientation: *(x,*(y,z)) = x + 2y + 4z + 21 >= x + 2y + 2z + 14 = *(*(x,y),z) *(x,x) = 3x + 7 >= x = x problem: Qed