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Related papers: A note on the codegree of finite groups

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We prove that if the average of the degrees of the irreducible characters of a finite group $G$ is less than 16/5, then $G$ is solvable. This solves a conjecture of I.M. Isaacs, M. Loukaki, and the first author. We discuss related…

Group Theory · Mathematics 2013-12-06 Alexander Moretó , Hung Ngoc Nguyen

Let $G$ be a finite group and ${\rm cd}(G)$ will be the set of the degrees of the complex irreducible characters of $G$. Also let ${\rm cod}(G)$ be the set of codegrees of the irreducible characters of $G$. The Taketa problem conjectures if…

Group Theory · Mathematics 2021-07-06 Mahtab Delfani , Mohsen Ghasemi , Somayeh Hekmatara

Let $G$ be a $p$-group and let $\chi$ be an irreducible character of $G$. The codegree of $\chi$ is given by $|G:\text{ker}(\chi)|/\chi(1)$. If $G$ is a maximal class $p$-group that is normally monomial or has at most three character…

Group Theory · Mathematics 2018-09-21 Sarah Croome , Mark L. Lewis

Let N be a normal subgroup of a finite group G and consider the set cd(G|N) of degrees of irreducible characters of G whose kernels do not contain N. A number of theorems are proved relating the set cd(G|N) to the structure of N. For…

Group Theory · Mathematics 2009-09-25 I. M. Isaacs , Greg Knutson

Let $G$ be a $p$-group and let $\chi$ be an irreducible character of $G$. The codegree of $\chi$ is given by $|G:\text{ker}(\chi)|/\chi(1)$. This paper investigates the relationship between the nilpotence class of a group and the inclusion…

Group Theory · Mathematics 2018-11-08 Sarah Croome , Mark L. Lewis

Let $G$ be a finite group and $\chi\in \irr(G)$. The codegree of $\chi$ is defined as $\cod(\chi)=\frac{|G:\ker(\chi)|}{\chi(1)}$ and $\cod(G)=\{\cod(\chi) \ |\ \chi\in \irr(G)\}$ is called the set of codegrees of $G$. In this paper, we…

Group Theory · Mathematics 2022-11-11 Hongning Wang , Xuning Zhang , Selina Zhang , Michelle Chen

Let $ G $ be a finite group and $ \chi \in \mathrm{Irr}(G) $. Define $ \mathrm{cv}(G)=\{\chi(g)\mid \chi \in \mathrm{Irr}(G), g\in G \} $, $ \mathrm{cv}(\chi)=\{\chi(g)\mid g\in G \} $ and denote $ \mathrm{dl}(G) $ by the derived length of…

Group Theory · Mathematics 2025-04-01 Sesuai Y. Madanha , X. Mbaale , Tendai M. Mudziiri Shumba

The character codegree of an irreducible character of a finite group $G$ is given by the index of its kernel in $G$ upon the character degree. We compute the codegrees of irreducible characters of VZ and Camina $p$-groups, and also obtain…

Group Theory · Mathematics 2026-05-26 Ayush Udeep

Let N be a minimal normal nonabelian subgroup of a finite group G. We will show that there exists a nontrivial irreducible character of N of degree at least 5 which is extendible to G. This result will be used to settle two open questions…

Group Theory · Mathematics 2010-04-16 Kay Magaard , Hung P. Tong-Viet

There has been some interest on how the average character degree affects the structure of a finite group. We define, and denote by $ \mathrm{anz}(G) $, the average number of zeros of characters of a finite group $ G $ as the number of zeros…

Group Theory · Mathematics 2021-06-30 Sesuai Y. Madanha

For an irreducible character $\chi$ of a finite group $G$, its kernel is defined as $\text{ker }\chi=\{g\in G: \chi(g)=\chi(1)\}$. In this paper we characterize the finite groups of prime power order(for odd prime) in which kernels of all…

Group Theory · Mathematics 2025-12-23 Nabajit Talukdar

We study the zero-sharing behavior among irreducible characters of a finite group. For symmetric groups $S_n$, it is proved that, with one exception, any two irreducible characters have at least one common zero. To further explore this…

Group Theory · Mathematics 2024-11-20 Nguyen N. Hung , Alexander Moretó , Lucia Morotti

We prove that there exists an integer-valued function f on positive integers such that if a finite group G has at most k real-valued irreducible characters, then |G/Sol(G)| is at most f(k), where Sol(G) denotes the largest solvable normal…

Group Theory · Mathematics 2019-05-28 Nguyen Ngoc Hung , A. A. Schaeffer Fry , Hung P. Tong-Viet , C. Ryan Vinroot

Let $G$ be a $p$-group and let $\chi$ be an irreducible character of $G$. The codegree of $\chi$ is given by $|G:\text{ker}(\chi)|/\chi(1)$. Du and Lewis have shown that a $p$-group with exactly three codegrees has nilpotence class at most…

Group Theory · Mathematics 2019-01-23 Sarah Croome , Mark L. Lewis

The covering number of a non-linear character $\chi$ of a finite group $G$ is the least positive integer $k$ such that every irreducible character of $G$ occurs in $\chi^k$. We determine the covering numbers of irreducible characters of the…

Representation Theory · Mathematics 2024-07-08 Rijubrata Kundu , Velmurugan S

We study the solvable groups $G$ that have an irreducible character $\chi\in \Irr(G)$ such that $\chi \bar{\chi}$ has at most two non-principal irreducible constituents.

Group Theory · Mathematics 2007-05-23 Edith Adan-Bante

Let $G$ be a finite group. Denoting by ${\rm{cd}}(G)$ the set of the degrees of the irreducible complex characters of $G$, we consider the {\it character degree graph} of $G$: this is the (simple, undirected) graph whose vertices are the…

Group Theory · Mathematics 2022-09-16 S. Dolfi , E. Pacifici , L. Sanus

Let $G$ be a finite $p$-group and $\chi,\psi$ be irreducible characters of $G$. We study the character $\chi\psi$ when $\chi\psi$ has at most $p-1$ distinct irreducible constituents.

Group Theory · Mathematics 2007-05-23 Edith Adan-Bante

Let G be a finite group. Denoting by cd(G) the set of degrees of the irreducible complex characters of G, we consider the character degree graph of G: this is the (simple undirected) graph whose vertices are the prime divisors of the…

Group Theory · Mathematics 2022-09-16 Silvio Dolfi , Emanuele Pacifici , Lucia Sanus , Victor Sotomayor

We prove that the order of a finite group $G$ with trivial solvable radical is bounded above in terms of ${\rm acd}(G)$, the average degree of the irreducible characters. It is not true that the index of the Fitting subgroup is bounded…

Group Theory · Mathematics 2022-10-04 Alexander Moretó