Periodic and subharmonic solutions for second-order nonlinear difference equations
This paper proves the existence and multiplicity of periodic and subharmonic solutions for second-order nonlinear difference equations by using the critical point method. The main approach used in our paper is a variational technique and the Linking Theorem. One of our results generalizes and improves the result in the literature.
periodic and subharmonic solutions second-order nonlinear difference equations discrete variational theory 39a11