English
Related papers

Related papers: Divisible design Cayley digraphs

200 papers

In this paper, we classify reflexible regular Cayley maps for dihedral groups.

Combinatorics · Mathematics 2015-04-22 István Kovács , Young Soo Kwon

The distinguishing number (index) $D(G)$ ($D'(G)$) of a graph $G$ is the least integer $d$ such that $G$ has an vertex labeling (edge labeling) with $d$ labels that is preserved only by a trivial automorphism. In this paper, we investigate…

Combinatorics · Mathematics 2017-04-14 Saeid Alikhani , Samaneh Soltani

We classify the distance-regular Cayley graphs with least eigenvalue $-2$ and diameter at most three. Besides sporadic examples, these comprise of the lattice graphs, certain triangular graphs, and line graphs of incidence graphs of certain…

Combinatorics · Mathematics 2016-04-28 Alireza Abdollahi , Edwin van Dam , Mojtaba Jazaeri

A geometric method for obtaining an infinite family of Cayley digraphs of constant density on finite Abelian groups is presented. The method works for any given degree and it is based on consecutive dilates of a minimum distance diagram…

Combinatorics · Mathematics 2021-04-23 F. Aguiló , M. A. Fiol , S. Pérez

We study triangle decompositions of graphs. We consider constructions of classes of graphs where every edge lies on a triangle and the addition of the minimum number of multiple edges between already adjacent vertices results in a strongly…

Combinatorics · Mathematics 2021-08-23 C. M. Mynhardt , A. K. Wright

The isomorphism problem of Cayley graphs has been well studied in the literature, such as characterizations of CI (DCI)-graphs and CI (DCI)-groups. In this paper, we generalize these to vertex-transitive graphs and establish parallel…

Combinatorics · Mathematics 2016-03-29 Jing Chen , Binzhou Xia

The Divisibility Graph of a finite group $G$ has vertex set the set of conjugacy class lengths of non-central elements in $G$ and two vertices are connected by an edge if one divides the other. We determine the connected components of the…

Group Theory · Mathematics 2016-12-15 Adeleh Abdolghafourian , Mohammad A. Iranmanesh , Alice C. Niemeyer

The results of computer searches for large graphs with given (small) degree and diameter are presented. The new graphs are Cayley graphs of semidirect products of cyclic groups and related groups. One fundamental use of our ``dense graphs''…

Combinatorics · Mathematics 2008-02-03 Michael J. Dinneen , Paul R. Hafner

In [Distrance-regular Cayley graphs on dihedral groups, J. Combin. Theory Ser B 97 (2007) 14--33], Miklavi\v{c} and Poto\v{c}nik proposed the problem of characterizing distance-regular Cayley graphs, which can be viewed as an extension of…

Combinatorics · Mathematics 2023-08-29 Xiongfeng Zhan , Lu Lu , Xueyi Huang

Given positive integers $k$ and $n$, we present methods to construct all groups of order at most $n$ that contain a Cayley set of size $k$, and to enumerate the Cayley sets of order $k$ in a given group, up to the action of the automorphism…

Combinatorics · Mathematics 2025-12-08 Rhys J. Evans , Primož Potočnik

We introduce a family of graphs that generalises the class of Cayley graphs. For non-empty subsets L, R of a group G, the two-sided Cayley graph 2SC(G;L,R) is the directed graph with vertex set G and an arc from x to y if and only if…

Combinatorics · Mathematics 2014-01-14 Moharram N. Iradmusa , Cheryl E. Praeger

This paper investigates the enumeration of Cayley digraphs, focusing on counting Cayley digraphs on dihedral groups up to CI-isomorphism. By leveraging the Cauchy-Frobenius Lemma and properties of automorphisms, we derive an explicit…

Combinatorics · Mathematics 2025-07-30 Zai Ping Lu , Jia Yin Xie , Jin-Hua Xie

In this paper, we try to determine exact or bounds on the choosability, or list chromatic numbers of some Cayley graphs, typically some Unitary Cayley graphs and Cayley graphs on Dihedral groups.

Combinatorics · Mathematics 2024-02-27 Prajnanaswaroopa S

A mixed graph can be seen as a type of digraph containing some edges (two opposite arcs). Here we introduce the concept of sequence mixed graphs, which is a generalization of both sequence graphs and iterated line digraphs. These structures…

Combinatorics · Mathematics 2016-10-13 C. Dalfó , M. A. Fiol , N. López

For every odd prime power $q$, a family of pairwise nonisomorphic normal arc-transitive divisible design Cayley digraphs with isomorphic neighborhood designs over a Heisenberg group of order $q^3$ is constructed. It is proved that these…

Combinatorics · Mathematics 2024-11-11 Mikhail Muzychuk , Grigory Ryabov

Mixed graphs can be seen as digraphs that have both arcs and edges (or digons, that is, two opposite arcs). In this paper, we consider the case in which such graphs are Cayley graphs of Abelian groups. These groups can be constructed by…

Combinatorics · Mathematics 2020-05-20 C. Dalfó , M. A. Fiol , N. López

A k-regular graph on v vertices is a divisible design graph with parameters (v, k, lambda_1 ,lambda_2, m, n) if its vertex set can be partitioned into m classes of size n, such that any two different vertices from the same class have…

Combinatorics · Mathematics 2021-12-01 Vladislav V. Kabanov

The split quartic Cayley algebra is a structurable algebra which has been used to give constructions of Lie algebras of type D4. Here, we calculate its group of automorphisms, its algebra of derivations and its gradings.

Rings and Algebras · Mathematics 2023-02-07 Victor Blasco , Alberto Daza-Garcia

We show that the directed labelled Cayley graphs coincide with the rooted deterministic vertex-transitive simple graphs. The Cayley graphs are also the strongly connected deterministic simple graphs of which all vertices have the same cycle…

Discrete Mathematics · Computer Science 2016-09-28 Didier Caucal

Let $p$ be an odd prime, and $D_{2p}=\langle \tau,\sigma\mid \tau^p=\sigma^2=e,\sigma\tau\sigma=\tau^{-1}\rangle$ the dihedral group of order $2p$. In this paper, we provide the number of (connected) Cayley (di-)graphs on $D_{2p}$ up to…

Combinatorics · Mathematics 2016-12-13 Xueyi Huang , Qiongxiang Huang