  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).
