%0 Journal Article %T A necessary and a sufficient condition for the existence of the positive radial solutions to Hessian equations and systems with weights %A Dragos-Patru Covei %J Mathematics %D 2015 %I arXiv %X In this article we consider the existence of positive radial solutions for Hessian equations and systems with weights and we give a necessary condition as well as a sufficient condition for a positive radial solution to be large. The method of proving theorems is essentially based on a successive approximation. Our results complete and improve a recently work published by Zhang and Zhou (Existence of entire positive k-convex radial solutions to Hessian equations and systems with weights, Applied Mathematics Letters, Volume 50, December 2015, Pages 48--55). %U http://arxiv.org/abs/1508.07426v1