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Related papers: Polytopality and Cartesian products of graphs

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A graph is well-dominated if all its minimal dominating sets have the same cardinality. In this paper we prove that at least one factor of every connected, well-dominated Cartesian product is a complete graph, which then allows us to give a…

Combinatorics · Mathematics 2023-10-31 Kirsti Kuenzel , Douglas F. Rall

Modern methods of graph theory describe a graph up to isomorphism, which makes it difficult to create mathematical models for visualizing graph drawings on a plane. The topological drawing of the planar part of a graph allows representing…

Combinatorics · Mathematics 2024-08-01 Sergey Kurapov , Maxim Davidovsky

Firstly, for a general graph, we find a recursion formula on the number of Hamiltonian cycles and one on cycles. By this result, we give some new polynomial invariants. Secondly, we give a condition to tell whether a polynomial defined by…

Combinatorics · Mathematics 2017-06-30 Yi Bo

Let $G$ be an undirected graph of order $n$ and let $C_i$ be an $i$-cycle graph. $G$ is called pancyclic if $G$ contains a $C_i$ for any $i\in \{3,4,\ldots,n\}$. We show that the pancyclicity of specific Cayley graphs and the Cartesian…

Combinatorics · Mathematics 2023-09-06 Yusaku Nishimura

Several variants of hypergraph products have been introduced as generalizations of the strong and direct products of graphs. Here we show that only some of them are associative. In addition to the Cartesian product, these are the minimal…

Combinatorics · Mathematics 2015-11-24 Richard H. Hammack , Marc Hellmuth , Lydia Ostermeier , Peter F. Stadler

This article studies automorphism groups of graph products of arbitrary groups. We completely characterise automorphisms that preserve the set of conjugacy classes of vertex groups as those automorphisms that can be decomposed as a product…

Group Theory · Mathematics 2019-08-07 Anthony Genevois , Alexandre Martin

We study graph products of groups from the viewpoint of measured group theory. We first establish a full measure equivalence classification of graph products of countably infinite groups over finite simple graphs with no transvection and no…

Group Theory · Mathematics 2024-01-10 Amandine Escalier , Camille Horbez

We investigate the uniqueness of factorisation of possibly disconnected finite graphs with respect to the Cartesian, the strong and the direct product. It is proved that if a graph has $n$ connected components, where $n$ is prime, or…

Combinatorics · Mathematics 2011-03-04 Christiaan E. van de Woestijne

We prove that graph products of sofic groups are sofic, as are graphs of groups for which vertex groups are sofic and edge groups are amenable.

Group Theory · Mathematics 2016-01-20 Laura Ciobanu , Derek F. Holt , Sarah Rees

We provide an explicit construction that allows one to easily decompose a graph braid group as a graph of groups. This allows us to compute the braid groups of a wide range of graphs, as well as providing two general criteria for a graph…

Group Theory · Mathematics 2023-09-15 Daniel Berlyne

Recently, Braunstein et al. [1] introduced normalized Laplacian matrices of graphs as density matrices in quantum mechanics and studied the relationships between quantum physical properties and graph theoretical properties of the underlying…

Quantum Physics · Physics 2011-11-15 Chai Wah Wu

Polytopes from subgraph statistics are important in applications and conjectures and theorems in extremal graph theory can be stated as properties of them. We have studied them with a view towards applications by inscribing large explicit…

Combinatorics · Mathematics 2011-08-22 Alexander Engström , Patrik Norén

Planar locally finite graphs which are almost vertex transitive are discussed. If the graph is 3-connected and has at most one end then the group of automorphisms is a planar discontinuous group and its structure is well-known. A general…

Group Theory · Mathematics 2009-05-08 M. J. Dunwoody

We introduce a homotopy theory of digraphs (directed graphs) and prove its basic properties, including the relations to the homology theory of digraphs constructed by the authors in previous papers. In particular, we prove the homotopy…

Algebraic Topology · Mathematics 2014-07-02 Alexander Grigor'yan , Yong Lin , Yuri Muranov , Shing-Tung Yau

The orbit graph of a k-orbit polytope is a graph on k nodes that shows how the flag orbits are related by flag adjacency. Using orbit graphs, we classify k-orbit polytopes and determine when a k-orbit polytope is i-transitive. We then…

Combinatorics · Mathematics 2013-06-10 Gabe Cunningham

For $d \ge 2$, we show that all graphs of $d$-polytopes have a Hamiltonian line graph if and only if $d \ne 3$: We exhibit a graph of a $3$-polytope on $252$ vertices whose line graph does not even have Hamiltonian paths. Adapting a…

Combinatorics · Mathematics 2025-07-03 Bruno Benedetti , Marta Pavelka

Motivated by the concept of well-covered graphs, we define a graph to be well-bicovered if every vertex-maximal bipartite subgraph has the same order (which we call the bipartite number). We first give examples of them, compare them with…

Combinatorics · Mathematics 2019-09-18 Wayne Goddard , Kirsti Kuenzel , Eileen Melville

A graph with a semiregular group of automorphisms can be thought of as the derived cover arising from a voltage graph. Since its inception, the theory of voltage graphs and their derived covers has been a powerful tool used in the study of…

Combinatorics · Mathematics 2019-10-21 Primoz Potocnik , Micael Toledo

The paper describes a construction of abstract polytopes from Cayley graphs of symmetric groups. Given any connected graph G with p vertices and q edges, we associate with G a Cayley graph of the symmetric group S_p and then construct a…

Deciding whether a graph can be embedded in a grid using only unit-length edges is NP-complete, even when restricted to binary trees. However, it is not difficult to devise a number of graph classes for which the problem is polynomial, even…

Data Structures and Algorithms · Computer Science 2012-04-13 Vinícius G. P. de Sá , Guilherme D. da Fonseca , Raphael Machado , Celina M. H. de Figueiredo