English
Related papers

Related papers: Construction of Directed Strongly Regular Graphs a…

200 papers

Many well-known graph drawing techniques, including force directed drawings, spectral graph layouts, multidimensional scaling, and circle packings, have algebraic formulations. However, practical methods for producing such drawings…

Computational Geometry · Computer Science 2016-03-22 Michael J. Bannister , William E. Devanny , David Eppstein , Michael T. Goodrich

Binomial Cayley graphs are obtained by considering the binomial coefficient of the weight function of a given Cayley graph and a natural number. We introduce these objects and study two families: one associated with symmetric groups and the…

Combinatorics · Mathematics 2024-09-06 Bernat Bassols-Cornudella , Francesco Viganò

Leavitt path algebras associate to directed graphs a $\mathbb Z$-graded algebra and in their simplest form recover the Leavitt algebras $L(1,k)$. In this note, we first study this $\mathbb Z$-grading and characterize the ($\mathbb…

Rings and Algebras · Mathematics 2011-11-02 R. Hazrat

In this paper, firstly, we provide some necessary and sufficient conditions for generalized Cayley graphs on abelian groups to be bipartite. Secondly, we deduce several necessary and sufficient conditions for generalized Cayley graphs on…

Combinatorics · Mathematics 2024-12-18 Liao Qianfen , Liu Weijun , Zhang Pengli

A graph is called a GRR if its automorphism group acts regularly on its vertex-set. Such a graph is necessarily a Cayley graph. Godsil has shown that there are only two infinite families of finite groups that do not admit GRRs : abelian…

Combinatorics · Mathematics 2013-10-03 Joy Morris , Pablo Spiga , Gabriel Verret

Mixed graphs can be seen as digraphs with arcs and edges (or digons, that is, two opposite arcs). In this paper, we consider the case where such graphs are bipartite and in which the undirected and directed degrees are one. The best graphs,…

Combinatorics · Mathematics 2024-03-29 C. Dalfó , G. Erskine , G. Exoo , M. A. Fiol , J. Tuite

The Directed Power Graph of a group is a graph whose vertex set is the elements of the group, with an edge from $x$ to $y$ if $y$ is a power of $x$. The \textit{Power Graph} of a group can be obtained from the directed power graph by…

Combinatorics · Mathematics 2020-12-07 Amrita Acharyya , Allen Williams

We determine new upper bounds for the clique numbers of strongly regular graphs in terms of their parameters. These bounds improve on the Delsarte bound for infinitely many feasible parameter tuples for strongly regular graphs, including…

Combinatorics · Mathematics 2019-01-31 Gary R. W. Greaves , Leonard H. Soicher

We introduce and study a strong "thin triangle"' condition for directed graphs, which generalises the usual notion of hyperbolicity for a metric space. We prove that finitely generated left cancellative monoids whose right Cayley graphs…

Group Theory · Mathematics 2014-10-14 Robert Gray , Mark Kambites

When one studies geometric properties of graphs, local finiteness is a common implicit assumption, and that of transitivity a frequent explicit one. By compactness arguments, local finiteness guarantees several regularity properties. It is…

Combinatorics · Mathematics 2017-01-06 Sébastien Martineau

It is known that the automorphism group of the elementary abelian $2$-group $Z_2^n$ is isomorphic to the general linear group $GL(n,F_2)$ of degree $n$ over $F_2$. Let $W$ be the collection of permutation matrices of order $n$. It is clear…

Combinatorics · Mathematics 2018-09-18 Lu Lu , Qiongxiang Huang , Jiangxia Hou

Isomorphic factorizations of complete graphs originate from the seminal work of Frank Harary and collaborators, who initiated the systematic study of decompositions of complete graphs into pairwise isomorphic spanning subgraphs. In this…

Combinatorics · Mathematics 2026-03-09 Huye Chen , Jingjian Li , Hao Yu , Zitong Yu

This paper proposes a family of permutation-invariant graph embeddings, generalizing the Skew Spectrum of graphs of Kondor & Borgwardt (2008). Grounded in group theory and harmonic analysis, our method introduces a new class of graph…

Machine Learning · Computer Science 2025-05-30 Armando Bellante , Martin Plávala , Alessandro Luongo

A straight-line drawing of a graph is a monotone drawing if for each pair of vertices there is a path which is monotonically increasing in some direction, and it is called a strongly monotone drawing if the direction of monotonicity is…

Computational Geometry · Computer Science 2016-01-08 Stefan Felsner , Alexander Igamberdiev , Philipp Kindermann , Boris Klemz , Tamara Mchedlidze , Manfred Scheucher

In this work, we try to enunciate the Total chromatic number of some Cayley graphs like the Cayley graph on Symmetric group, Alternating group, Dihedral group with respect to some generating sets and some other regular graphs.

Combinatorics · Mathematics 2023-07-04 Prajnanaswaroopa S

We show that (n,2^n) additive codes over GF(4) can be represented as directed graphs. This generalizes earlier results on self-dual additive codes over GF(4), which correspond to undirected graphs. Graph representation reduces the…

Combinatorics · Mathematics 2011-03-17 Lars Eirik Danielsen , Matthew G. Parker

This paper deals with some of the algebraic properties of Sierpi\'nski graphs and a family of regular generalized Sierpi\'nski graphs. For the family of regular generalized Sierpi\'nski graphs, we obtain their spectrum and characterize…

We establish an Expander Mixing Lemma for directed graphs in terms of the eigenvalues of an associated asymmetric transition probability matrix, extending the classical spectral inequality to the asymmetric setting. As an application, we…

Combinatorics · Mathematics 2025-11-04 Rebecca Carter

We introduce and investigate generalizations of interval and proper interval graphs to simplicial complexes, including strong interval, unit interval, and under closed variants. Through equivalent combinatorial and algebraic…

Combinatorics · Mathematics 2025-10-21 Fahimeh Khosh-Ahang Ghasr

Jaeger's directed cycle double cover conjecture can be formulated as a problem of existence of special perfect matchings in a class of graphs that we call hexagon graphs. In this work, we explore the structure of hexagon graphs. We show…

Combinatorics · Mathematics 2013-11-05 Andrea Jiménez , Mihyun Kang , Martin Loebl
‹ Prev 1 8 9 10 Next ›