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This article produces a complete list of all maximal subgroups of the finite simple groups of type $F_4$, $E_6$, and twisted $E_6$ over all finite fields. Along the way, we determine the collection of Lie primitive almost simple subgroups…

Group Theory · Mathematics 2025-05-19 David A. Craven

In this note we describe the finite groups $G$ having $|G|-2$ cyclic subgroups. This partially solves the open problem in the end of \cite{3}.

Group Theory · Mathematics 2016-05-04 Marius Tărnăuceanu

All finite simple groups are determined with the property that every Galois orbit on conjugacy classes has size at most 4. From this we list all finite simple groups $G$ for which the normalized group of central units of the integral group…

Group Theory · Mathematics 2019-06-04 Victor Bovdi , Thomas Breuer , Attila Maróti

A subgroup of a finite group G is said to be second maximal if it is maximal in every maximal subgroup of G that contains it. A question which has received considerable attention asks: can every positive integer occur as the number of the…

Group Theory · Mathematics 2008-10-22 Alberto Basile

In this note, we classify all finite groups having exactly 6, 7 or 8 cyclic subgroups. This gives a partial answer to the open problem posed by Tarnauceanu (Amer. Math. Monthly, 122 (2015), 275-276). As a consequence of our results, we also…

Group Theory · Mathematics 2018-05-08 Hemant Kalra

We characterize finite $p$-groups $G$ of order up to $p^7$ for which the group of central automorphisms fixing the center element-wise is of minimum possibe order.

Group Theory · Mathematics 2015-03-17 Deepak Gumber , Mahak Sharma

We study the number of cylic subgroups in finite groups and get that $G$ has $|G|-3$ cyclic subgroups if and only if $G \cong D_{10}$ or $Q_8$.

Group Theory · Mathematics 2016-05-03 Wei Zhou

Let $G$ be a finite non-abelian group and $\kappa_1(G)$ the number of conjugate classes of minimal non-abelian subgroups of $G$. The structure of $G$ with $\kappa_1(G)=1$ is determined. In the case of $G$ being the $p$-groups, the structure…

Group Theory · Mathematics 2025-08-14 Haipeng Qu , Junqiang Zhang

For a finite group $G$ let $\sigma(G)$ (the "sum" of $G$) be the least number of proper subgroups of $G$ whose set-theoretical union is equal to $G$, and $\sigma(G)=\infty$ if $G$ is cyclic. We say that a group $G$ is $\sigma$-elementary if…

Group Theory · Mathematics 2011-12-30 Martino Garonzi

In his paper "Finite groups have many conjugacy classes" (J. London Math. Soc (2) 46 (1992), 239-249), L. Pyber proved the to date best general lower bounds for the number of conjugacy classes of a finite group in terms of the order of the…

Group Theory · Mathematics 2008-12-16 Thomas Michael Keller

Let $k(G)$ be the number of conjugacy classes of finite groups $G$ and $\pi_e(G)$ be the set of the orders of elements in $G$. Then there exists a non-negative integer $k$ such that $k(G)=|\pi_e(G)|+k$. We call such groups to be $co(k)$…

Group Theory · Mathematics 2007-05-23 Xianglin Du , Wujie Shi

Marius T\u{a}rn\u{a}uceanu described the finite groups $G$ having $|G|-1$ cyclic subgroups. We describe the finite groups $G$ having $|G|-\Delta$ cyclic subgroups for $\Delta=2, 3, 4$ and $5$.

Group Theory · Mathematics 2018-06-19 Richard Belshoff , Joe Dillstrom , Les Reid

A pseudomodular group is a discrete subgroup $\Gamma \leq PGL(2,\mathbb{Q})$ which is not commensurable with $PSL(2,\mathbb{Z})$ and has cusp set precisely $\mathbb{Q}\cup\{\infty\}$. The existence of such groups was proved by Long and…

Geometric Topology · Mathematics 2020-05-26 Carmen Galaz-García

We classify all finite groups with five relative commutativity degrees. Also, we give a partial answer to our previous conjecture on a lower bound of the number of relative commutativity degrees of finite groups.

Group Theory · Mathematics 2019-12-11 Mohammad Farrokhi Derakhshandeh Ghouchan

We determine all finite subgroups of simple algebraic groups that have irreducible centralizers - that is, centralizers whose connected component does not lie in a parabolic subgroup.

Group Theory · Mathematics 2016-06-10 Martin W. Liebeck , Adam R. Thomas

We continue the investigation, that began in [3] and [4], into finite groups whose set of nontrivial conjugacy class sizes form an arithmetic progression. Let $G$ be a finite group and denote the set of conjugacy class sizes of $G$ by ${\rm…

Group Theory · Mathematics 2020-09-14 Alan R. Camina , Rachel D. Camina

We prove that every finitely generated soluble group which is not virtually abelian has a subgroup of one of a small number of types.

Group Theory · Mathematics 2015-10-09 Tara Brough , Derek Holt

Two elements in a group $G$ are said to $z$-equivalent or to be in the same $z$-class if their centralizers are conjugate in $G$. In \cite{kkj}, it was proved that a non-abelian $p$-group $G$ can have at most $\frac{p^k-1}{p-1} +1$ number…

Group Theory · Mathematics 2016-05-05 Shivam Arora , Krishnendu Gongopadhyay

The problem of enumeration of conjugacy classes of finite abelian subgroups of the mapping class group $\mathcal{M}_{\sigma}$ of a compact closed surface $X$ of genus $\sigma$ is considered. A complete method of enumeration is achieved for…

Algebraic Topology · Mathematics 2014-10-01 S. Allen Broughton , A. Wootton

We classify, up to conjugacy, the finite (constant) subgroups G of adjoint absolutely simple algebraic groups of type $A_1$ over an arbitrary field $k$ of characteristic not 2.

Algebraic Geometry · Mathematics 2013-08-15 Mario Garcia-Armas