English
Related papers

Related papers: Unlabeled Signed Graph Coloring

200 papers

In this paper, we define the Mycielskian of a signed graph and discuss the properties of balance and switching in the Mycielskian of a given signed graph. We provide a condition for ensuring the Mycielskian of a balanced signed graph…

Combinatorics · Mathematics 2023-05-26 Albin Mathew , Germina K. A.

In 2015, Matthias Beck and his team developed a computer program in SAGE which efficiently determines the number of signed proper $k$-colorings for a given signed graph. In this article, we determine the number of different signatures on…

Combinatorics · Mathematics 2018-12-21 Deepak , Bikash Bhattacharjya

In this paper, we study the Cartesian product of signed graphs as defined by Germina, Hameed and Zaslavsky (2011). Here we focus on its algebraic properties and look at the chromatic number of some Cartesian products. One of our main…

Combinatorics · Mathematics 2020-10-21 Dimitri Lajou

The chromatic polynomial is characterized as the unique polynomial invariant of graphs, compatible with two interacting bialgebras structures: the first coproduct is given by partitions of vertices into two parts, the second one by a…

Rings and Algebras · Mathematics 2021-05-05 Loïc Foissy

Stanley in his paper [Stanley, Richard P.: Acyclic orientations of graphs In: Discrete Mathematics 5 (1973), Nr. 2, S. 171-178.] provided interpretations of the chromatic polynomial when it is substituted with negative integers. Greene and…

Combinatorics · Mathematics 2019-03-19 Bishal Deb

In this paper, we extend the notion of labeled partitions with ordinary permutations to colored permutations in the sense that the colors are endowed with a cyclic structure. We use labeled partitions with colored permutations to derive the…

Combinatorics · Mathematics 2008-10-21 William Y. C. Chen , Henry Y. Gao , Jia He

We introduce joins of signed graphs and explore the chromatic number of the all-positive and all-negative joins. We prove an analogue to the theorem that the chromatic number of the join of two graphs equals the sum of their chromatic…

Combinatorics · Mathematics 2020-06-01 Amelia R. W. Mattern

We present an elementary construction of an uncountably chromatic graph without uncountable, infinitely connected subgraphs.

Combinatorics · Mathematics 2024-05-20 Nathan Bowler , Max Pitz

In this note we introduce a representation of simple undirected graphs in terms of polynomials and obtain a unique code for a simple undirected graph.

Combinatorics · Mathematics 2013-07-02 Shamik Ghosh , Raibatak Sen Gupta , M. K. Sen

We introduce a class of pairs of graphs consisting of two cliques joined by an arbitrary number of edges. The members of a pair have the property that the clique-bridging edge-set of one graph is the complement of that of the other. We…

Combinatorics · Mathematics 2011-06-08 Adam Bohn

We extend the theory of circular game chromatic numbers to signed graphs by defining the invariant $\chi_c^g(G,\sigma)$ for signed graphs $(G,\sigma)$. Our analysis establishes tight bounds dependent on the structural properties of the…

Combinatorics · Mathematics 2025-05-29 Pie Desire Ebode Atanhgana

Signed graphs are graphs whose edges get a sign $+1$ or $-1$ (the signature). Signed graphs can be studied by means of graph matrices extended to signed graphs in a natural way. Recently, the spectra of signed graphs have attracted much…

Combinatorics · Mathematics 2019-07-11 Francesco Belardo , Sebastian M. Cioabă , Jack H. Koolen , Jianfeng Wang

A proper vertex colouring of a graph is \emph{nested} if the vertices of each of its colour classes can be ordered by inclusion of their open neighbourhoods. Through a relation to partially ordered sets, we show that the nested chromatic…

Combinatorics · Mathematics 2013-06-04 David Cook

A signed graph product is defined for a new product, and initially the unsigned graph product's Laplacian spectrum and signless Laplacian spectrum are found. Next, for the signed graph product, the adjacency spectrum, Laplacian spectrum,…

Combinatorics · Mathematics 2024-05-16 Bishal Sonar , Ravi Srivastava

A recent result of Lofano and Paolini expresses the characteristic polynomial of a real hyperplane arrangement in terms of a projection statistic on the regions of the arrangement. We use this result to give an alternative proof for Greene…

Combinatorics · Mathematics 2025-10-27 Neha Goregaokar

In earlier work we introduced the graph bracket polynomial of graphs with marked vertices, motivated by the fact that the Kauffman bracket of a link diagram D is determined by a looped, marked version of the interlacement graph associated…

Geometric Topology · Mathematics 2010-07-02 Lorenzo Traldi

There are many variations on partition functions for graph homomorphisms or colorings. The case considered here is a counting or hard constraint problem in which the range or color graph carries a free and vertex transitive Abelian group…

Combinatorics · Mathematics 2012-04-06 Eric Babson , Matthias Beck

The fractional and circular chromatic numbers are the two most studied non-integral refinements of the chromatic number of a graph. Starting from the definition of a coloring base of a graph, which originated in work related to ergodic…

Combinatorics · Mathematics 2021-01-12 Pablo Candela , Carlos Catala , Robert Hancock , Adam Kabela , Daniel Kral , Ander Lamaison , Lluis Vena

The (torsion) complexity of a finite signed graph is defined to be the order of the torsion subgroup of the abelian group presented by its Laplacian matrix. When $G$ is $d$-periodic (i.e., $G$ has a free ${\mathbb Z}^d$-action by graph…

Geometric Topology · Mathematics 2020-08-14 Daniel S. Silver , Susan G. Williams

The chromatic number, which refers to the minimum number of colours required to colour the vertices of graphs properly, is one of the most central notions of the graph chromatic theory. Several of its aspects of interest have been…

Discrete Mathematics · Computer Science 2022-05-12 Julien Bensmail , François Dross , Nacim Oijid , Éric Sopena