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In this paper, we prove that all finite solvable groups satisfy the Isaacs-Seitz conjecture namely the derived lenght of a finite solvable group G is less than or equal to the number of distinct irreducible complex character degrees of G.

Group Theory · Mathematics 2017-05-30 Burcu Çınarcı , Temha Erkoç

We show the existence of a unitriangular basic set for unipotent blocks simple reductive groups of classical type in bad characteristic with some exceptions. Then,we introduce an algorithm to count irreducible unipotent Brauer characters…

Representation Theory · Mathematics 2018-10-16 Reda Chaneb

Motivated by the reduction techniques involving character triples for the local-global conjectures, we show that a blockwise relation between module triples is a consequence of a derived equivalence with additional properties. Moreover, we…

Representation Theory · Mathematics 2020-08-27 Andrei Marcus , Virgilius-Aurelian Minuta

Let $U_n$ denote the group of upper $n \times n$ unitriangular matrices over a fixed finite field $\mathbb{F}$ of order $q$. That is, $U_n$ consists of upper triangular $n \times n$ matrices having every diagonal entry equal to $1$. It is…

Group Theory · Mathematics 2023-05-23 Maria Loukaki

Let $G$ be a finite $p$-solvable group, where $p$ is an odd prime. We establish a connection between extendible irreducible characters of subgroups of $G$ that lie under monomial characters of $G$ and nilpotent subgroups of $G$. We also…

Group Theory · Mathematics 2023-05-23 Maria Loukaki

In this short note, it is proved that both the number of primitive characters and the number of quasi-primitive characters in a finite group $G$ is divisible by $|G:G'|$, where $G'$ is the derived subgroup of $G$.

Group Theory · Mathematics 2023-06-01 Riad Youmbai , Gang Chen

Let $G$ be a nonabelian finite group and let $d$ be an irreducible character degree of $G$. Then there is a positive integer $e$ so that $|G| = d(d+e)$. Snyder has shown that if $e > 1$, then $|G|$ is bounded by a function of $e$. This…

Group Theory · Mathematics 2014-11-13 Mark L. Lewis

Let $G$ be a finite group. The bipartite divisor graph for the set of irreducible complex character degrees is the undirected graph with vertex set consisting of the prime numbers dividing some character degree and of the non-identity…

Group Theory · Mathematics 2019-06-21 Roghayeh Hafezieh , Pablo Spiga

In 1961, Solomon gave upper and lower bounds for the sum of all the entries in the character table of a finite group in terms of elementary properties of the group. In a different direction, we consider the ratio of the character table sum…

Representation Theory · Mathematics 2024-06-11 Arvind Ayyer , Hiranya Kishore Dey , Digjoy Paul

Let $U(q)$ be a Sylow $p$-subgroup of the Chevalley groups $D_4(q)$ where $q$ is a power of a prime $p$. We describe a construction of all complex irreducible characters of $U(q)$ and obtain a classification of these irreducible characters…

Representation Theory · Mathematics 2009-11-12 Frank Himstedt , Tung Le , Kay Magaard

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

Let $G$ be a finite solvable group with disconnected character degree graph $\Delta(G)$. Under these conditions, it follows from a result of P\'alfy that $\Delta(G)$ consists of two connected components. Another result of P\'alfy's gives an…

Combinatorics · Mathematics 2025-04-03 Mark L. Lewis , Andrew Summers

It is shown that, for the block matrices belonging to $M(nd,\mathbb{C})$ with commuting and normal block entries of dimension $d$, the separability of such a block matrices is equivalent to its semi-positive definity. The separability…

Quantum Physics · Physics 2015-10-14 Marek Mozrzymas , Adam Rutkowski , Michał Studziński

Recently, a construction of group divisible designs (GDDs) derived from the decoding of quadratic residue (QR) codes was given. In this paper, we extend the idea to obtain a new family of GDDs, which is also involved with a well-known…

Combinatorics · Mathematics 2018-09-05 Yu-pei Huang , Chia-an Liu , Yaotsu Chang , Chong-Dao Lee

Amdeberhan recently proposed certain equalities between sums in the character table of symmetric groups. These equalities are between signed column sums in the character table, summing over the rows labeled by partitions in $\Ev$, where…

Combinatorics · Mathematics 2025-09-24 David J. Hemmer , Armin Straub , Karlee Westrem

Let $G$ be an arbitrary finite group and fix a prime number $p$. The McKay conjecture asserts that $G$ and the normalizer in $G$ of a Sylow $p$-subgroup have equal numbers of irreducible characters with degrees not divisible by $p$. The…

Group Theory · Mathematics 2007-05-23 I. M. Isaacs , G. Navarro

We call an irreducible character $p$-singular if $p$ divides its degree. We prove a number of equivalent conditions for a character of the symmetric group $S_n$ to be $p$-singular, involving a certain family of conjugacy classes. This…

Representation Theory · Mathematics 2015-12-15 Lucia Morotti

When n is odd, consider the finite general linear and unitary groups of rank n, extended by the inverse transpose automorphism. There are elements in the extended groups which square to a regular unipotent element, and we evaluate the…

Representation Theory · Mathematics 2007-05-23 Rod Gow , C. Ryan Vinroot

We study blocks all of whose height zero ordinary characters have the same degree. We suspect that these might be the Broue-Puig nilpotent blocks.

Group Theory · Mathematics 2009-09-24 Gunter Malle , Gabriel Navarro

In this article we extend independent results of Lusztig and H\'ezard concerning the existence of irreducible characters of finite reductive groups, (defined in good characteristic and arising from simple algebraic groups), satisfying a…

Representation Theory · Mathematics 2014-04-01 Jay Taylor