English
Related papers

Related papers: Finite Groups With Two Irredundant Covers

200 papers

A finite presentation < X | R > of a finite group is called `just finite' if removing any relation from R results in a presentation for an infinite group. It has been an open question (Kourovka Notebook, Problem 21.10) whether every finite…

Group Theory · Mathematics 2026-05-12 Marc Lackenby

The spectrum of a finite group is the set of element orders of this group. The main goal of this paper is to survey results concerning recognition of finite simple groups by spectrum, in particular, to list all finite simple groups for…

Group Theory · Mathematics 2024-06-06 Maria A. Grechkoseeva , Victor D. Mazurov , Wujie Shi , Andrey V. Vasil'ev , Nanying Yang

The nonsoluble length $\lambda (G)$ of a finite group $G$ is defined as the number of nonsoluble factors in a shortest normal series each of whose factors either is soluble or is a direct product of nonabelian simple groups. The generalized…

Group Theory · Mathematics 2014-05-09 E. I. Khukhro , P. Shumyatsky

The covering number of a nontrivial finite group $G$, denoted $\sigma(G)$, is the smallest number of proper subgroups of $G$ whose set-theoretic union equals $G$. In this article, we focus on a dual problem to that of covering numbers of…

We classify the finite groups whose non-linear irreducible characters that are not conjugate under the natural Galois action have distinct degrees, therefore extending the results in Berkovich et al. [Proc. Amer. Math. Soc. {\bf 115}…

Group Theory · Mathematics 2016-03-11 Silvio Dolfi , Manoj K. Yadav

Given a finite group $G$, we denote by $L(G)$ the subgroup lattice of $G$ and by ${\cal CD}(G)$ the Chermak-Delgado lattice of $G$. In this note, we determine the finite groups $G$ such that $|{\cal CD}(G)|=|L(G)|-k$, $k=1,2$.

Group Theory · Mathematics 2022-09-05 Georgiana Fasolă , Marius Tărnăuceanu

In this paper, we provide new criteria for the solvability and supersolvability of a finite group based on its number of cyclic subgroups. A finite group G is called n-cyclic if it contains n cyclic subgroups. This paper also partially…

Group Theory · Mathematics 2026-04-28 Angsuman Das , Khyati Sharma

This expository article revolves around the question to find short presentations of finite simple groups. This subject is one of the most active research areas of group theory in recent times. We bring together several known results on…

Group Theory · Mathematics 2020-05-19 Yash Arora , Anupam Singh

Every mathematician is familiar with the beautiful structure of finite commutative groups. What is less well known is that finite commutative semigroups also have a neat and well-described structure. We prove this in an efficient fashion.…

Group Theory · Mathematics 2025-05-02 Marcel Wild

A self-similar group of finite type is the profinite group of all automorphisms of a regular rooted tree that locally around every vertex act as elements of a given finite group of allowed actions. We provide criteria for determining when a…

Group Theory · Mathematics 2014-09-02 Ievgen V. Bondarenko , Igor O. Samoilovych

Groups of finite type (also called finitely constrained groups), introduced by Grigorchuk, are known to be the closure of regular branch groups. This article explores many of their properties. Firstly, we prove that being finitely…

Group Theory · Mathematics 2025-09-05 Santiago Radi

Let $k$ be a perfect field such that for every $n$ there are only finitely many field extensions, up to isomorphism, of $k$ of degree $n$. If $G$ is a reductive algebraic group defined over $k$, whose characteristic is very good for $G$,…

Group Theory · Mathematics 2020-05-19 Shripad M. Garge , Anupam Singh

For each nonnegative integer $g$, we classify the ramification types and monodromy groups of indecomposable coverings of complex curves $f: X\to Y$ where $X$ has genus $g$, under the hypothesis that $n:=\deg(f)$ is sufficiently large and…

Algebraic Geometry · Mathematics 2024-03-27 Danny Neftin , Michael E. Zieve

We study systematically groups whose marked finite quotients form a recursive set. We give several definitions, and prove basic properties of this class of groups, and in particular emphasize the link between the growth of the depth…

Group Theory · Mathematics 2021-10-27 Emmanuel Rauzy

Given any finitely presented group G we find a triangular algebra such that has two presentations, one with fundamental group G and another with trivial group. Thus proving that given a collection G1,...,Gn of finitely presented groups…

Group Theory · Mathematics 2008-07-30 Jorge Nicolas Lopez

In this report we summarize this work, all finite simple groups $G$ can determined uniformly using their orders $|G|$ and the set $\pi_e(G)$ of their element orders.

Group Theory · Mathematics 2013-03-19 Wujie Shi

Let R be a unitary ring of finite cardinality P^k, where p is a prime number and $p\nmid k$. We show that if the group of units of $R$ has at most one subgroup of order $p$, then $R\cong A\bigoplus B,$ where $B$ is a finite ring of order…

Rings and Algebras · Mathematics 2021-05-31 Mostafa Amini , Mohsen Amiri

In this article, we show that a group $G$ is the union of two proper subsemigroups if and only if $G$ has a nontrivial left-orderable quotient. Furthermore, if $G$ is the union of two proper semigroups, then there exists a minimum normal…

Group Theory · Mathematics 2020-02-13 Casey Donoven

The multiplicative group of a finite field is well known to be cyclic; in this note, we determine the finite fields whose multiplicative groups are direct sum indecomposable. We obtain our classification using a direct argument and also as…

Number Theory · Mathematics 2014-07-15 Sunil Chebolu , Keir Lockridge

Let G be an abelian group and let lambda be the smallest rank of any group whose direct sum with a free group is isomorphic to G. If lambda is uncountable, then G has lambda pairwise disjoint, non-free subgroups. There is an example where…

Logic · Mathematics 2007-05-23 Andreas Blass , Saharon Shelah
‹ Prev 1 8 9 10 Next ›