Existence of homoclinic orbit for second-order nonlinear difference equation

Abstract

By using the Mountain Pass Theorem, we establish some existence criteria to guarantee the second-order nonlinear difference equation $\Delta \left[p(t)\Delta u(t-1)\right] +f(t,u(t))=0$ has at least one homoclinic orbit, where $t\in \mathbb{Z},\ u\in \mathbb{R}$