Odd complete bipartite minors in graphs with independence number two

Abstract

Recently, Chen and Deng have proved that every graph $G$ with independence number two contains $K_{\ell,\chi(G)- \ell}$ as a minor for each integer $\ell$ with $1\leq\ell < \chi(G)$. In this paper, we extend this result to odd minor version. That is, we prove that each graph $G$ with independence number two contains $K_{\ell,\chi(G)- \ell}$ as an odd minor for each integer $\ell$ with $1\leq\ell < \chi(G)$.