Green’s functions for fractional difference equations with Dirichlet boundary conditions

Abstract

This article is devoted to deduce the expression and the main properties of the Green’s function related to a general constant coefficients fractional difference equation coupled to Dirichlet conditions. In particular, it is proved that such function has constant sign on their set of definition and, moreover, it satisfies some additional strong sign conditions that are fundamental to define suitable cones, where to ensure the existence of solutions of nonlinear problems.