20.500.12556/RUL-116658 Nonlinear, nonhomogeneous Robin problems with indefinite potential and general reaction We consider a nonlinear elliptic equation driven by a nonhomogeneous differential operator plus an indefinite potential. On the reaction term we impose conditions only near zero. Using variational methods, together with truncation and perturbation techniques and critical groups, we produce three nontrivial solutions with sign information. In the semilinear case we improve this result by obtaining a second nodal solution for a total of four nontrivial solutions. Finally, under a symmetry condition on the reaction term, we generate a whole sequence of distinct nodal solutions. nonhomogeneous differential operator nonlinear regularity theory constant sign and nodal solutions infinitely many nodal solutions critical groups true false true Angleški jezik Ni določen Članek v reviji 2020-06-01 11:21:54 2020-06-01 11:21:56 2022-08-28 03:51:32 0000-00-00 00:00:00 2020 0 0 Str. 823-857 iss. 3 Vol. 81 June 2020 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 517.956.2 0095-4616 10.1007/s00245-018-9521-x 18436441 24984064 RAZ_Papageorgiou_Nikolaos_2020.pdf RAZ_Papageorgiou_Nikolaos_2020.pdf 1 DAED8F9F6A9231D71F9095E53D9875EE fcab699d9e74bf1eb16fd2258a26ff636f1b8ed760f9980ca36b0c6dc6d1884f fb6c57c1-a1b8-11eb-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=130306 Pedagoška fakulteta Fakulteta za matematiko in fiziko 0 0 0