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Related papers: The Engel graph of almost simple groups

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We study the connectivity of proper power graphs of some family of finite groups including nilpotent groups, groups with a non-trivial partition, and symmetric and alternating groups.

Group Theory · Mathematics 2014-01-28 Alireza Doostabadi , Mohammad Farrokhi Derakhshandeh Ghouchan

The Gruenberg-Kegel graph $\Gamma(G)$ of a finite group $G$ is the graph whose vertex set is the set of prime divisors of $|G|$ and in which two distinct vertices $r$ and $s$ are adjacent if and only if there exists an element of order $rs$…

Group Theory · Mathematics 2023-02-01 Natalia V. Maslova , Viktor V. Panshin , Alexey M. Staroletov

In this paper we investigate the $directed$ $normalizing$ $graph$ associated with a group $G$, defined as the simple directed graph whose vertices are the elements of $G$, with an arrow from $x$ to $y$ whenever the subgroup $\langle x…

Group Theory · Mathematics 2025-11-04 Costantino Delizia , Michele Gaeta , Carmine Monetta

The nilpotent graph of a group $G$ is the simple and undirected graph whose vertices are the elements of $G$ and two distinct vertices are adjacent if they generate a nilpotent subgroup of $G$. Here we discuss some topological properties of…

Group Theory · Mathematics 2025-02-11 Costantino Delizia , Michele Gaeta , Mark L. Lewis , Carmine Monetta

We say that an element $g$ of a group $G$ is almost right Engel if there is a finite set ${\mathscr R}(g)$ such that for every $x\in G$ all sufficiently long commutators $[...[[g,x],x],\dots ,x]$ belong to ${\mathscr R}(g)$, that is, for…

Group Theory · Mathematics 2018-07-18 E. I. Khukhro , P. Shumyatsky

We associate a graph ${\mathcal N}_{S}$ with a semigroup $S$ (called the upper non-nilpotent graph of $S$). The vertices of this graph are the elements of $S$ and two vertices are adjacent if they generate a semigroup that is not nilpotent…

Group Theory · Mathematics 2014-03-03 E. Jespers , M. H. Shahzamanian

The power graph of a group $G$, denoted as $P(G)$, constitutes a simple undirected graph characterized by its vertex set $G$. Specifically, vertices $a,b$ exhibit adjacency exclusively if $a$ belongs to the cyclic subgroup generated by $b$…

Group Theory · Mathematics 2024-01-23 Dhawlath. G , Raja. V

Let $G$ be a finite group. A number of graphs with the vertex set $G$ have been studied, including the power graph, enhanced power graph, and commuting graph. These graphs form a hierarchy under the inclusion of edge sets, and it is useful…

Combinatorics · Mathematics 2021-12-07 G. Arunkumar , Peter J. Cameron , Rajat Kanti Nath , Lavanya Selvaganesh

A finite group is called $\psi$-divisible iff $\psi(H)|\psi(G)$ for any subgroup $H$ of a finite group $G$. Here, $\psi(G)$ is the sum of element orders of $G$. For now, the only known examples of such groups are the cyclic ones of…

Group Theory · Mathematics 2022-03-02 Mihai-Silviu Lazorec

The enhanced power graph of a group $G$ is a graph with vertex set $G,$ where two distinct vertices $x$ and $y$ are adjacent if and only if there exists an element $w$ in $G$ such that both $x$ and $y$ are powers of $w.$ In this paper, we…

Combinatorics · Mathematics 2024-05-03 Sudip Bera , Hiranya Kishore Dey

The commuting graph of a non-abelian group is a simple graph in which the vertices are the non-central elements of the group, and two distinct vertices are adjacent if and only if they commute. In this paper, we classify (up to isomorphism)…

Group Theory · Mathematics 2013-11-26 Ashish Kumar Das , Deiborlang Nongsiang

Let $H$ be a subgroup of a finite non-abelian group $G$ and $g \in G$. Let $Z(H, G) = \{x \in H : xy = yx, \forall y \in G\}$. We introduce the graph $\Delta_{H, G}^g$ whose vertex set is $G \setminus Z(H, G)$ and two distinct vertices $x$…

Group Theory · Mathematics 2020-12-03 Monalisha Sharma , Rajat Kanti Nath

For an element $g$ of a group $G$, a right Engel sink of $g$ is a subset of $G$ containing all sufficiently long commutators $[...[[g ,x],x],\dots ,x]$ for all $x\in G$. A left Engel sink of $g$ is a subset of $G$ containing all…

Group Theory · Mathematics 2026-05-12 Evgeny Khukhro , Pavel Shumyatsky

For a group $G,$ the enhanced power graph of $G$ is a graph with vertex set $G$ in which two distinct elements $x, y$ are adjacent if and only if there exists an element $w$ in $G$ such that both $x$ and $y$ are powers of $w.$ The proper…

Combinatorics · Mathematics 2021-08-12 Sudip Bera , Hiranya Kishore Dey

The enhanced power graph, $\mathcal{E}(G)$, of a group $G$ has vertex set $G$ and two elements are adjacent if they generate a cyclic subgroup. In the case of finite groups, we identify some striking and unexpected properties of these…

Group Theory · Mathematics 2025-10-22 Daniela Bubboloni , Francesco Fumagalli , Cheryl E. Praeger

A word-graph Gw is a digraph represented by a word w such that the vertex-set V(Gw) is the alphabet of w and the edge-set E(Gw) is determined by non-identical adjacent letter pairs in w. In this paper we study the strong-connectivity of…

Combinatorics · Mathematics 2011-08-31 Edward J. L. Bell , Damon Berridge , Paul Rayson

In this paper we describe all the finite almost simple groups whose Gruenberg--Kegel graphs coincide with Gruenberg--Kegel graphs of finite solvable groups.

Group Theory · Mathematics 2016-06-14 Ilya B. Gorshkov , Natalia V. Maslova

There are a variety of ways to associate directed or undirected graphs to a group. It may be interesting to investigate the relations between the structure of these graphs and characterizing certain properties of the group in terms of some…

Group Theory · Mathematics 2017-05-23 A. R. Moghaddamfar , S. Rahbariyan , W. J. Shi

Let $G$ be a finite, non-abelian group of the form $G = A N$, where $A \leq G$ is abelian, and $N \trianglelefteq G$ is cyclic. We prove that the commuting graph $\Gamma(G)$ of $G$ is either a connected graph of diameter at most four, or…

Group Theory · Mathematics 2024-11-27 Timo Velten

Let $p$ be a prime and let $G$ be a subgroup of a Sylow pro-$p$ subgroup of the group of automorphisms of the $p$-adic tree. We prove that if $G$ is fractal and $|G':\mathrm{st}_G(1)'|=\infty$, then the set $L(G)$ of left Engel elements of…

Group Theory · Mathematics 2018-04-03 Gustavo A. Fernández-Alcober , Albert Garreta , Marialaura Noce