Electronic Journal of Differential Equations,
Vol. 2013 (2013), No. 166, pp. 1-7.

Title: Existence and multiplicity of solutions for semilinear
       differential equations with subquadratic potentials
        
Authors: Chengyue Li   (Minzu Univ, Beijing, China)
         Mengmeng Wang (Minzu Univ, Beijing, China)
         Zhiwei Xiao   (Minzu Univ, Beijing, China)

Abstract:
 Existence and multiplicity of nontrivial solutions of a class of semilinear
 differential equations with subquadratic potentials are studied using
 Clark's theorem. As an application of the above results,
 periodic solutions for a second Hamiltonian systems are studied.

Submitted April 2, 2013. Published July 21, 2013.
Math Subject Classifications: 58E05, 34C37, 70H05.
Key Words: Subquadratic potentials; Clark theorem; critical points;
           Hamiltonian systems.