YES Problem: a__zeros() -> cons(0(),zeros()) a__tail(cons(X,XS)) -> mark(XS) mark(zeros()) -> a__zeros() mark(tail(X)) -> a__tail(mark(X)) mark(cons(X1,X2)) -> cons(mark(X1),X2) mark(0()) -> 0() a__zeros() -> zeros() a__tail(X) -> tail(X) Proof: Matrix Interpretation Processor: dim=1 interpretation: [tail](x0) = 2x0 + 4, [mark](x0) = 4x0, [a__tail](x0) = 2x0 + 4, [cons](x0, x1) = x0 + 4x1, [zeros] = 0, [0] = 0, [a__zeros] = 0 orientation: a__zeros() = 0 >= 0 = cons(0(),zeros()) a__tail(cons(X,XS)) = 2X + 8XS + 4 >= 4XS = mark(XS) mark(zeros()) = 0 >= 0 = a__zeros() mark(tail(X)) = 8X + 16 >= 8X + 4 = a__tail(mark(X)) mark(cons(X1,X2)) = 4X1 + 16X2 >= 4X1 + 4X2 = cons(mark(X1),X2) mark(0()) = 0 >= 0 = 0() a__zeros() = 0 >= 0 = zeros() a__tail(X) = 2X + 4 >= 2X + 4 = tail(X) problem: a__zeros() -> cons(0(),zeros()) mark(zeros()) -> a__zeros() mark(cons(X1,X2)) -> cons(mark(X1),X2) mark(0()) -> 0() a__zeros() -> zeros() a__tail(X) -> tail(X) Matrix Interpretation Processor: dim=3 interpretation: [1 0 0] [tail](x0) = [0 0 0]x0 [0 0 0] , [1 1 1] [0] [mark](x0) = [1 1 1]x0 + [0] [0 0 0] [1], [1 0 0] [0] [a__tail](x0) = [0 0 0]x0 + [0] [0 0 0] [1], [1 0 1] [1 0 0] [0] [cons](x0, x1) = [0 1 0]x0 + [0 0 1]x1 + [0] [0 0 0] [0 0 0] [1], [0] [zeros] = [0] [1], [0] [0] = [0] [0], [1] [a__zeros] = [1] [1] orientation: [1] [0] a__zeros() = [1] >= [1] = cons(0(),zeros()) [1] [1] [1] [1] mark(zeros()) = [1] >= [1] = a__zeros() [1] [1] [1 1 1] [1 0 1] [1] [1 1 1] [1 0 0] [1] mark(cons(X1,X2)) = [1 1 1]X1 + [1 0 1]X2 + [1] >= [1 1 1]X1 + [0 0 1]X2 + [0] = cons(mark(X1),X2) [0 0 0] [0 0 0] [1] [0 0 0] [0 0 0] [1] [0] [0] mark(0()) = [0] >= [0] = 0() [1] [0] [1] [0] a__zeros() = [1] >= [0] = zeros() [1] [1] [1 0 0] [0] [1 0 0] a__tail(X) = [0 0 0]X + [0] >= [0 0 0]X = tail(X) [0 0 0] [1] [0 0 0] problem: mark(zeros()) -> a__zeros() mark(cons(X1,X2)) -> cons(mark(X1),X2) mark(0()) -> 0() a__tail(X) -> tail(X) Matrix Interpretation Processor: dim=3 interpretation: [1 0 0] [tail](x0) = [0 0 0]x0 [0 0 0] , [1 0 0] [mark](x0) = [0 1 1]x0 [0 0 0] , [1 0 0] [1] [a__tail](x0) = [0 0 0]x0 + [1] [0 0 0] [0], [1 1 1] [1 0 0] [1] [cons](x0, x1) = [0 0 0]x0 + [0 0 0]x1 + [0] [0 0 0] [0 0 0] [0], [1] [zeros] = [0] [0], [0] [0] = [0] [0], [0] [a__zeros] = [0] [0] orientation: [1] [0] mark(zeros()) = [0] >= [0] = a__zeros() [0] [0] [1 1 1] [1 0 0] [1] [1 1 1] [1 0 0] [1] mark(cons(X1,X2)) = [0 0 0]X1 + [0 0 0]X2 + [0] >= [0 0 0]X1 + [0 0 0]X2 + [0] = cons(mark(X1),X2) [0 0 0] [0 0 0] [0] [0 0 0] [0 0 0] [0] [0] [0] mark(0()) = [0] >= [0] = 0() [0] [0] [1 0 0] [1] [1 0 0] a__tail(X) = [0 0 0]X + [1] >= [0 0 0]X = tail(X) [0 0 0] [0] [0 0 0] problem: mark(cons(X1,X2)) -> cons(mark(X1),X2) mark(0()) -> 0() Matrix Interpretation Processor: dim=3 interpretation: [1 0 1] [mark](x0) = [0 0 1]x0 [1 0 1] , [1 0 0] [1 0 0] [0] [cons](x0, x1) = [0 0 0]x0 + [0 0 0]x1 + [1] [0 0 1] [0 0 0] [1], [1] [0] = [0] [0] orientation: [1 0 1] [1 0 0] [1] [1 0 1] [1 0 0] [0] mark(cons(X1,X2)) = [0 0 1]X1 + [0 0 0]X2 + [1] >= [0 0 0]X1 + [0 0 0]X2 + [1] = cons(mark(X1),X2) [1 0 1] [1 0 0] [1] [1 0 1] [0 0 0] [1] [1] [1] mark(0()) = [0] >= [0] = 0() [1] [0] problem: mark(0()) -> 0() Matrix Interpretation Processor: dim=3 interpretation: [1 0 0] [1] [mark](x0) = [0 0 0]x0 + [0] [0 0 0] [0], [0] [0] = [0] [0] orientation: [1] [0] mark(0()) = [0] >= [0] = 0() [0] [0] problem: Qed