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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

Given a finite group G, let cd(G) denote the set of degrees of the irreducible complex characters of G. The character degree graph of G is defined as the simple undirected graph whose vertices are the prime divisors of the numbers in cd(G),…

Group Theory · Mathematics 2018-09-28 Zeinab Akhlaghi , Carlo Casolo , Silvio Dolfi , Emanuele Pacifici , Lucia Sanus

We prove that there is a unique graph with four edges which is the Gruenberg-Kegel graph of a solvable cut group. This contributes to the classification of the Gruenberg-Kegel graphs of solvable cut groups initiated in [A. B\"achle, A.…

Group Theory · Mathematics 2026-04-03 Sara C. Debón , Diego García-Lucas , Ángel del Río

The power graph $\mathcal{P}(G)$ of a group $G$ is the simple graph with vertex set $G$ and two vertices are adjacent whenever one of them is a positive power of the other. In this paper, for a finite noncyclic nilpotent group $G$, we study…

Combinatorics · Mathematics 2021-08-16 Ramesh Prasad Panda , Kamal Lochan Patra , Binod Kumar Sahoo

Let G be a finite group and let cd(G) be the set of all complex irreducible character degrees of G Let \rho(G) be the set of all primes which divide some character degree of G. The prime graph \Delta(G) attached to G is a graph whose vertex…

Group Theory · Mathematics 2013-03-15 Hung P. Tong-Viet

The enhanced power graph of a finite group $G$, denoted by $\mathcal{P}_E(G)$, is the simple undirected graph whose vertex set is $G$ and two distinct vertices $x, y$ are adjacent if $x, y \in \langle z \rangle$ for some $z \in G$. In this…

Group Theory · Mathematics 2022-07-13 Parveen , Jitender Kumar , Siddharth Singh , Xuanlong Ma

This paper provides a bridge between two active areas of research, the spectrum (set of element orders) and the power graph of a finite group. The order sequence of a finite group $G$ is the list of orders of elements of the group, arranged…

Group Theory · Mathematics 2025-10-22 Peter J. Cameron , Hiranya Kishore Dey

Let $G$ be a finite group. Then we denote $\psi(G) = \sum_{x\in G}o(x)$ where $o(x)$ is the order of the element $x$ in $G$. In this paper we characterize some finite $p$-groups ($p$ a prime) by $\psi$ and their orders.

Group Theory · Mathematics 2019-03-15 S. M. Jafarian Amiri , Mohsen Amiri

For the first time we represent every finite group in the form of a graph in this book. The authors choose to call these graphs as identity graph, since the main role in obtaining the graph is played by the identity element of the group.…

General Mathematics · Mathematics 2009-06-30 W. B. Vasantha Kandasamy , Florentin Smarandache

The $G$-graph $\Gamma(G,S)$ is a graph from the group $G$ generated by $S\subseteq G$, where the vertices are the right cosets of the cyclic subgroups $\langle s \rangle, s\in S$ with $k$-edges between two distinct cosets if there is an…

Combinatorics · Mathematics 2016-09-05 Lord Clifford Kavi

Let $A$ and $G$ be finite groups such that $A$ acts coprimely on $G$ by automorphisms, assume that $G$ has a maximal $A$-invariant subgroup $M$ that is a direct product of some isomorphic simple groups, we prove that if $G$ has a…

Group Theory · Mathematics 2025-02-07 Jiangtao Shi , Mengjiao Shan , Fanjie Xu

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

Let $G$ be a finite group. The solubility graph associated with the finite group $G$, denoted by $\Gamma_{\cal S}(G)$, is a simple graph whose vertices are the non-trivial elements of $G$, and there is an edge between two distinct elements…

Group Theory · Mathematics 2020-03-04 B. Akbari , Mark L. Lewis , J. Mirzajani , A. R. Moghaddamfar

Let $G$ be a finite group, and let ${\rm{cd}}(G)$ denote the set of degrees of the irreducible complex characters of $G$. Define then the character degree graph $\Delta(G)$ as the (simple undirected) graph whose vertices are the prime…

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

A graph is weakly perfect if its clique number and chromatic number are equal. We show that the enhanced power graph of a finite group $G$ is weakly perfect: its clique number and chromatic number are equal to the maximum order of an…

Combinatorics · Mathematics 2022-07-18 Peter J. Cameron , Veronica Phan

In this paper we study the description of the functional graphs associated with the power maps over finite groups. We present a structural result which describes the isomorphism class of these graphs for abelian groups and also for flower…

Discrete Mathematics · Computer Science 2022-09-08 Claudio Qureshi , Lucas Reis

Let $ H $ be a subgroup of a finite group $ G $. We say that $ H $ satisfies the partial $ \Pi $-property in $ G $ if there exists a $G$-chief series $ \varGamma_{G}: 1 =G_{0} < G_{1} < \cdot\cdot\cdot < G_{n}= G $ of $ G $ such that $ | G…

Group Theory · Mathematics 2024-07-16 Zhengtian Qiu , Adolfo Ballester-Bolinches

The spectrum $\omega(G)$ of a finite group $G$ is the set of element orders of $G$. If $\Omega$ is a non-empty subset of the set of natural numbers, $h(\Omega)$ stands for the number of isomorphism classes of finite groups $G$ with…

Group Theory · Mathematics 2007-05-23 A. R. Moghaddamfar , W. J. Shi

A classification is given of finite $k$-set-homogeneous graphs for $k\geqslant 2$, leading to a striking result that each finite $k$-set-homogeneous graph is $k$-homogeneous. It shows that $3$-set-homogeneous graphs are rare, consisting of…

Group Theory · Mathematics 2026-02-24 Cai Heng Li , Fu-Gang Yin , Jin-Xin Zhou

The commuting graph ${\Gamma(G)}$ of a group $G$ is the simple undirected graph with group elements as a vertex set and two elements $x$ and $y$ are adjacent if and only if $xy=yx$ in $G$. By eliminating the identity element of $G$ and all…

Combinatorics · Mathematics 2025-06-25 Siddharth Malviy , Vipul Kakkar