Integer-valued polynomials on valuation rings of global fields with prescribed lengths of factorizations.

Let V be a valuation ring of a global field K . We show that for all positive integers k and 1 < n 1 ≤ ⋯ ≤ n k there exists an integer-valued polynomial on V , that is, an element of Int ( V ) = { f ∈ K [ X ] ∣ f ( V ) ⊆ V } , which has precisely k essentially different factorizations into irreducible elements of Int ( V ) whose lengths are exactly n 1 , … , n k . In fact, we show more, namely that the same result holds true for every discrete valuation domain V with finite residue field such that the quotient field of V admits a valuation ring independent of V whose maximal ideal is principal or whose residue field is finite. If the quotient field of V is a purely transcendental extension of an arbitrary field, this property is satisfied. This solves an open problem proposed by Cahen, Fontana, Frisch and Glaz in these cases.