Multiple solutions for semilinear Robin problems with superlinear reaction and no symmetries

Abstract

We study a semilinear Robin problem driven by the Laplacian with a parametric superlinear reaction. Using variational tools from the critical point theory with truncation and comparison techniques, critical groups and flow invariance arguments, we show the existence of seven nontrivial smooth solutions, all with sign information and ordered. For more information see https://ejde.math.txstate.edu/Volumes/2021/12/abstr.html