YES Problem: rec[iter_0][3](0()) -> id() rec[iter_0][3](S(x14)) -> compS_f(rec[iter_0][3](x14)) compS_f[1](compS_f(x5),x3) -> compS_f[1](x5,S(x3)) compS_f[1](id(),x7) -> S(x7) main(0()) -> 0() main(S(x25)) -> compS_f[1](rec[iter_0][3](x25),0()) Proof: Matrix Interpretation Processor: dim=1 interpretation: [main](x0) = 2x0 + 2, [compS_f[1]](x0, x1) = 2x0 + 2x1 + 1, [compS_f](x0) = x0 + 4, [S](x0) = x0 + 4, [id] = 4, [rec[iter_0][3]](x0) = x0 + 2, [0] = 2 orientation: rec[iter_0][3](0()) = 4 >= 4 = id() rec[iter_0][3](S(x14)) = x14 + 6 >= x14 + 6 = compS_f(rec[iter_0][3](x14)) compS_f[1](compS_f(x5),x3) = 2x3 + 2x5 + 9 >= 2x3 + 2x5 + 9 = compS_f[1](x5,S(x3)) compS_f[1](id(),x7) = 2x7 + 9 >= x7 + 4 = S(x7) main(0()) = 6 >= 2 = 0() main(S(x25)) = 2x25 + 10 >= 2x25 + 9 = compS_f[1](rec[iter_0][3](x25),0()) problem: rec[iter_0][3](0()) -> id() rec[iter_0][3](S(x14)) -> compS_f(rec[iter_0][3](x14)) compS_f[1](compS_f(x5),x3) -> compS_f[1](x5,S(x3)) Matrix Interpretation Processor: dim=1 interpretation: [compS_f[1]](x0, x1) = x0 + x1 + 4, [compS_f](x0) = x0 + 4, [S](x0) = x0 + 4, [id] = 0, [rec[iter_0][3]](x0) = 7x0, [0] = 3 orientation: rec[iter_0][3](0()) = 21 >= 0 = id() rec[iter_0][3](S(x14)) = 7x14 + 28 >= 7x14 + 4 = compS_f(rec[iter_0][3](x14)) compS_f[1](compS_f(x5),x3) = x3 + x5 + 8 >= x3 + x5 + 8 = compS_f[1](x5,S(x3)) problem: compS_f[1](compS_f(x5),x3) -> compS_f[1](x5,S(x3)) Matrix Interpretation Processor: dim=3 interpretation: [1 0 1] [1 0 0] [compS_f[1]](x0, x1) = [0 0 0]x0 + [0 0 0]x1 [0 0 0] [0 0 0] , [1 0 1] [0] [compS_f](x0) = [0 0 0]x0 + [0] [0 0 0] [1], [1 0 0] [S](x0) = [0 0 0]x0 [0 0 0] orientation: [1 0 0] [1 0 1] [1] [1 0 0] [1 0 1] compS_f[1](compS_f(x5),x3) = [0 0 0]x3 + [0 0 0]x5 + [0] >= [0 0 0]x3 + [0 0 0]x5 = compS_f[1](x5,S(x3)) [0 0 0] [0 0 0] [0] [0 0 0] [0 0 0] problem: Qed