Computing the bound of an Ore polynomial. Applications to factorization

Abstract

We develop a fast algorithm for computing the bound of an Ore polynomial over a skew field, under mild conditions. As an application, we state a criterion for deciding whether a bounded Ore polynomial is irreducible, and we discuss a factorization algorithm. The asymptotic time complexity in the degree of the given Ore polynomial is studied. In the class of Ore polynomials over a finite field, our algorithm is an alternative to Giesbretch's one that reduces the complexity in the degree of the polynomial.