Character codegrees in finite groups

Abstract

For an irreducible character \chi of a finite group G, we define its codegree as \mathrm{c}\mathrm{o}\mathrm{d}\left(\chi \right)=\frac{|G:\ker \chi |}{\chi \left(1\right)}. In this paper, we introduce some known results and unsolved problems about character codegrees in finite groups.

Keywords

Finite group / character / character codegree

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