Damped vibration problems with nonlinearities being sublinear at both zero and infinity

摘要

In this paper, we study a class of damped vibration problems with nonlinearities being sublinear at both zero and infinity, and we obtain infinitely many nontrivial periodic solutions by using a variant fountain theorem. To the best of our knowledge, there is no published result concerning this case by this method. Copyright (c) 2015 John Wiley & Sons, Ltd.