English

On the sum of character codegrees of finite groups

Group Theory 2024-02-21 v1

Abstract

Let χ\chi be an irreducible character of a group G.G. We denote the sum of the codegrees of the irreducible characters of GG by Sc(G)=χIrr(G)cod(χ).S_c(G)=\sum_{\chi\in {\rm Irr}(G)}{\rm cod}(\chi). We consider the question if Sc(G)Sc(Cn)S_c(G)\leq S_c(C_n) is true for any finite group G,G, where n=Gn=|G| and CnC_n is a cyclic group of order n.n. We show this inequality holds for many classes of groups. In particular, we provide an affirmative answer for any finite group whose order is divisible by up to 99 primes. However, we show that the question does not hold true in all cases, by evidence of a counterexample.

Keywords

Cite

@article{arxiv.2402.12628,
  title  = {On the sum of character codegrees of finite groups},
  author = {Mark L. Lewis and Quanfu Yan},
  journal= {arXiv preprint arXiv:2402.12628},
  year   = {2024}
}