Multiple periodic solutions for superquadratic second-order discrete Hamiltonian systems

摘要

Some multiplicity results are obtained for periodic solutions of the nonautonomous superquadratic second-order discrete Hamiltonian systems Delta(2)u(t - 1) + Delta F(t, u(t)) = 0 for all t is an element of Z by using critical point theory, especially, a three critical points theorem proposed by Brezis and Nirenberg. (C) 2007 Elsevier Inc. All rights reserved.