Canad. Math. Bull. 53(2010), 347-359
Printed: Jun 2010
Nikolaos S. Papageorgiou
We consider semilinear periodic problems with the right-hand side nonlinearity satisfying a double resonance condition between two successive eigenvalues. Using a combination of variational and degree theoretic methods, we prove the existence of at least two nontrivial solutions.
double resonance, generalized LL-condition, Leray-Schauder degree, Cerami condition
34B15 - Nonlinear boundary value problems