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Related papers: Integral Cayley graphs and groups

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Renteln proved that the eigenvalues of the distance matrix of a Cayley graph of a real reflection group with respect to the set of all reflections are integral and provided a combinatorial formula for some such spectra. We prove the…

Combinatorics · Mathematics 2015-11-13 Briana Foster-Greenwood , Cathy Kriloff

A mixed graph is said to be integral if all the eigenvalues of its Hermitian adjacency matrix are integer. Let $\Gamma$ be an abelian group. The \textit{mixed Cayley graph} $Cay(\Gamma,S)$ is a mixed graph on the vertex set $\Gamma$ and…

Combinatorics · Mathematics 2021-06-29 Monu Kadyan , Bikash Bhattacharjya

All Cayley representations of the distant graph $\Gamma _Z$ over integers are characterized as Neumann subgroups of the extended modular group. Possible structures of Neumann subgroups are revealed and it is shown that every such a…

Group Theory · Mathematics 2020-10-20 Andrzej Matraś , Artur Siemaszko

Distance-regular graphs are a class of regualr graphs with pretty combinatorial symmetry. In 2007, Miklavi\v{c} and Poto\v{c}nik proposed the problem of charaterizing distance-regular Cayley graphs, which can be viewed as a natural…

Combinatorics · Mathematics 2023-11-15 Xueyi Huang , Lu Lu , Xiongfeng Zhan

Li and Praeger classified finite nonabelian simple groups, it has only one or two fusion classes of any certain value. As a by-product, they classified m-CI-groups, which is critical in the research of Cayley graphs. In the paper, we will…

Combinatorics · Mathematics 2019-10-16 Xiao-Min Zhu , Xu Yang

We present simple graph-theoretic characterizations of Cayley graphs for left-cancellative monoids, groups, left-quasigroups and quasigroups. We show that these characterizations are effective for the end-regular graphs of finite degree.

Discrete Mathematics · Computer Science 2018-03-26 Didier Caucal

It is shown that a Cayley multigraph over a group $G$ with generating multiset $S$ is integral (i.e., all of its eigenvalues are integers) if $S$ lies in the integral cone over the boolean algebra generated by the normal subgroups of $G$.…

Combinatorics · Mathematics 2012-09-25 Matt DeVos , Roi Krakovski , Bojan Mohar , Azhvan Sheikh Ahmady

We obtain a complete description of the planar cubic Cayley graphs, providing an explicit presentation and embedding for each of them. This turns out to be a rich class, comprising several infinite families. We obtain counterexamples to…

Group Theory · Mathematics 2015-03-18 Agelos Georgakopoulos

A positive integer $n$ is a Cayley number if every vertex-transitive graph of order $n$ is a Cayley graph. In 1983, Dragan Maru\v{s}i\v{c} posed the problem of determining the Cayley numbers. In this paper we give an infinite set $S$ of…

Combinatorics · Mathematics 2015-09-18 Edward Dobson , Pablo Spiga

We introduce the factorization graph of a finite group and study its connectedness and forbidden structures. We characterize all finite groups with connected factorization graphs and classify those with connected bipartite factorization…

Group Theory · Mathematics 2019-12-02 Mohammad Farrokhi Derakhshandeh Ghouchan , Ali Azimi

In this paper we introduce the concept of a Cayley graph automatic group (CGA group or graph automatic group, for short) which generalizes the standard notion of an automatic group. Like the usual automatic groups graph automatic ones enjoy…

Group Theory · Mathematics 2011-08-12 Olga Kharlampovich , Bakhadyr Khoussainov , Alexei Miasnikov

Evra, Feigon, Maurischat, and Parzanchevski (2023) introduced a biregular extension of Cayley graphs. In this paper, we reformulate their definition and provide some basic properties. We also show how these Cayley incidence graphs relate to…

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

We show that every non-trivial compact connected group and every non-trivial general or special linear group over an infinite field admits a generating set such that the associated Cayley graph has infinite diameter.

Group Theory · Mathematics 2019-01-30 Jakob Schneider

A few properties of unitary Cayley graphs are explored using their eigenvalues. It is shown that the adjacency algebra of a unitary Cayley graph is a coherent algebra. Finally, a class of unitary Cayley graphs that are distance regular are…

Number Theory · Mathematics 2017-07-11 A. Satyanarayana Reddy

Let $\Gamma$ be a finite graph and let $A(\Gamma)$ be its adjacency matrix. Then $\Gamma$ is {\it singular} if $A(\Gamma)$ is singular. The singularity of graphs is of certain interest in graph theory and algebraic combinatorics. Here we…

Combinatorics · Mathematics 2018-04-05 Johannes Siemons , Alexandre Zalesski

We show that a group admits a planar, finitely generated Cayley graph if and only if it admits a special kind of group presentation we introduce, called a planar presentation. Planar presentations can be recognised algorithmically. As a…

Combinatorics · Mathematics 2019-01-03 Agelos Georgakopoulos , Matthias Hamann

We show that for certain integers $n$, the problem of whether or not a Cayley digraph $\Gamma$ of $\mathbb Z_n$ is also isomorphic to a Cayley digraph of some other abelian group $G$ of order $n$ reduces to the question of whether or not a…

Combinatorics · Mathematics 2020-09-21 Edward Dobson , Joy Morris

Mirror graphs were introduced by Bre\v{s}ar et al. in 2004 as an intriguing class of graphs: vertex-transitive, isometrically embeddable into hypercubes, having a strong connection with regular maps and polytope structure. In this article…

Combinatorics · Mathematics 2016-09-05 Tilen Marc

We construct a 2-generated group $\Gamma $ such that its Cayley graph possesses finite connected subsets with arbitrarily big finite Heesch number.

Group Theory · Mathematics 2015-03-13 Azer Akhmedov