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Related papers: Balanced Cayley graphs and balanced planar graphs

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We show that every edge in a 2-edge-connected planar cubic graph is either contained in a 2-edge-cut or is a chord of some cycle that is contained in a 2-factor of the graph. As a consequence, we show that every edge in a cyclically…

Combinatorics · Mathematics 2022-10-19 Ajit Diwan

For a planar graph with a given f-vector $(f_{0}, f_{1}, f_{2}),$ we introduce a cubic polynomial whose coefficients depend on the f-vector. The planar graph is said to be real if all the roots of the corresponding polynomial are real. Thus…

Combinatorics · Mathematics 2018-03-29 M. R. Emamy-K. , Bahman Kalantari , Tatiana Correa

In a graph A, for each two arbitrary vertices g, h with d(g,h)=2,|MAg2h|=mAg2h is introduced the number of edges of A that are closer to g than to h. We say A is a 2-edge distance-balanced graph if we have mAg2h=mAh2g. In this article, we…

Combinatorics · Mathematics 2023-09-07 Zohreh Aliannejadi , Mehdi alaeiyan , Alireza Gilani , Jafar Asadpour

A graph $G$ on $n$ vertices with $k$ edges is $t$-edge-balanced if every graph on $n$ vertices with $t$ edges is contained in exactly the same number of subgraphs of $K_n$ isomorphic to $G$. Despite the existence of infinite families of…

Combinatorics · Mathematics 2026-05-19 Yeow Meng Chee

Median graphs are connected graphs in which for all three vertices there is a unique vertex that belongs to shortest paths between each pair of these three vertices. In this paper we provide several novel characterizations of planar median…

Combinatorics · Mathematics 2021-10-19 Carsten R. Seemann , Vincent Moulton , Peter F. Stadler , Marc Hellmuth

In this paper we introduce and study a type of Cayley graph -- subnormal Cayley graph. We prove that a subnormal 2-arc transitive Cayley graph is a normal Cayley graph or a normal cover of a complete bipartite graph $K_{p^d,p^d}$ with $p$…

Combinatorics · Mathematics 2021-01-13 Shu Jiao Song

We discuss functions from edges and vertices of an undirected graph to an Abelian group. Such functions, when the sum of their values along any cycle is zero, are called balanced labelings. The set of balanced labelings forms an Abelian…

Combinatorics · Mathematics 2013-06-28 Yonah Cherniavsky , Avraham Goldstein , Vadim E. Levit

The genus graphs have been studied by many authors, but just a few results concerning in special cases: Planar, Toroidal, Complete, Bipartite and Cartesian Product of Bipartite. We present here a derive general lower bound for the genus of…

General Topology · Mathematics 2016-01-05 J. E. Strapasson , S. I. R. Costa , M. M. S. Alves

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

The boxicity of a graph G is defined as the minimum integer k such that G is an intersection graph of axis-parallel k-dimensional boxes. Chordal bipartite graphs are bipartite graphs that do not contain an induced cycle of length greater…

Combinatorics · Mathematics 2009-06-04 L. Sunil Chandran , Mathew C. Francis , Rogers Mathew

It is shown that every 2-planar graph is quasiplanar, that is, if a simple graph admits a drawing in the plane such that every edge is crossed at most twice, then it also admits a drawing in which no three edges pairwise cross. We further…

Computational Geometry · Computer Science 2019-09-05 Michael Hoffmann , Csaba D. Tóth

A connected graph $\G$ is said to be {\it distance-balanced} whenever for any pair of adjacent vertices $u,v$ of $\G$ the number of vertices closer to $u$ than to $v$ is equal to the number of vertices closer to $v$ than to $u$. In…

Combinatorics · Mathematics 2011-02-02 Stefko Miklavic , Primoz Sparl

A graph is {\em near-bipartite} if its vertex set can be partitioned into an independent set and a set that induces a forest. It is clear that near-bipartite graphs are $3$-colorable. In this note, we show that planar graphs without cycles…

Combinatorics · Mathematics 2021-06-02 Runrun Liu , Gexin Yu

A 2-nearly Platonic graph of type (k|d) is a k-regular planar graph with f faces, f-2 of which are of degree d and the remaining two are of degrees m_1;m_2, both different from d. Such a graph is called balanced if m_1=m_2. We show that all…

Combinatorics · Mathematics 2020-03-02 D. Froncek , M. R. Khorsandi , S. R. Musawi , J. Qiu

A number of authors have studied the question of when a graph can be represented as a Cayley graph on more than one nonisomorphic group. The work to date has focussed on a few special situations: when the groups are $p$-groups; when the…

Combinatorics · Mathematics 2020-05-26 Joy Morris , Josip Smolcic

A number of authors have studied the question of when a graph can be represented as a Cayley graph on more than one nonisomorphic group. In this paper we give conditions for when a Cayley graph on an abelian group can be represented as a…

Combinatorics · Mathematics 2022-05-04 Joy Morris , Adrian Skelton

In this note we show that there is a cubic graph of girth $5$ that is not a subgraph of any minimal Cayley graph. On the other hand, we show that any Generalized Petersen Graph $G(n,k)$ with $\gcd(n,k)=1$ is an induced subgraph of a minimal…

Combinatorics · Mathematics 2025-10-08 Kolja Knauer , Alvaro Soto Gomez

A graph is near-bipartite if its vertex set can be partitioned into an independent set and a set which induces a forest. In this paper, planar graphs without cycles of length from 4 to 7 are shown to be near-bipartite.

Combinatorics · Mathematics 2022-04-21 Lili Hao , Weihua Yang , Shuang Zhao

A signed graph $(G,\sigma)$ is a graph $G$ together with an assignment $\sigma$ of either a positive sign or a negative sign to each edge. A signed graph is unbalanced if it contains a cycle with odd number of negative edges. The spectral…

Combinatorics · Mathematics 2026-04-17 Yiting Cai , Hongying Lin , Bo Zhou

A universal representation theorem is derived that shows any graph is the intersection graph of one chordal graph, a number of co-bipartite graphs, and one unit interval graph. Central to the the result is the notion of the clique cover…

Combinatorics · Mathematics 2015-04-21 Farhad Shahrokhi