Let P ⊂ R N be an integral convex polytope of dimension d and ∂P its boundary. (An integral convex polytope is a convex polytope all of whose vertices have integer coordinates.) Given integers n = 1, 2, . . ., we write i(P, n) for the number of integer points belonging to nP, where nP = {nα : α ∈ P}. In other words,