Filippakis, Michael E.Papageorgiou, Nikolaos S.2021-12-152021-12-152018-01-02Filippakis, M. E., & Papageorgiou, N. S. (2018). Resonant (p,q)-equations with Robin boundary condition. <i>Electronic Journal of Differential Equations, 2018</i>(01), pp. 1-24.1072-6691https://hdl.handle.net/10877/15056We consider a nonlinear nonhomogeneous Robin problem that has the sum of a p-Laplacian and a q-Laplacian (a (p,q)-equation). The reaction term is a Caratheodory function which is resonant at ±∞ with respect to any nonprincipal variational eigenvalue of the Robin p-Laplacian. Using variational methods and Morse theory (critical groups), we show the existence of at least three nontrivial smooth solutions.Text24 pages1 file (.pdf)enAttribution 4.0 International(p,q)-Laplace differential operatorResonanceCritical groupsMultiple solutionsNonlinear regularityArticle