We establish some new criteria to guarantee nonexistence, existence, and multiplicity of nontrivial periodic solutions of some semilinear sixth-order difference equations by using minmax method, index theory, and variational technique. Our results only make some assumptions on the period , which are very easy to verify and rather relaxed.
"Nontrivial Periodic Solutions to Some Semilinear Sixth-Order Difference Equations." Abstr. Appl. Anal. 2014 1 - 8, 2014. https://doi.org/10.1155/2014/359105