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Related papers: Matroids of Gain Signed Graphs

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Let $\Sigma=(\Gamma, \sigma)$ is a signed graph(or sigraph in short), where $\Gamma$ is a underlying graph of $\Sigma$ and $\sigma:E\longrightarrow \{+, -\}$ is a function. Consider $\Gamma=Cay(\mathbb{Z}_{p_{1}}\times…

Combinatorics · Mathematics 2020-11-12 Mohammad A. Iranmanesh , Nasrin Moghaddami

Le n be any positive integer. A hyperbinary expansion of n is are presentation of n as sum of powers of 2, each power being used at most twice. In this paper we study some properties of a suitable edge-coloured and vertex-weighted oriented…

Combinatorics · Mathematics 2016-10-05 M. Brunetti , A. D'Aniello

We study additively graceful labelings of signed graphs on stars and double stars. While the case of signed stars is straightforward, the problem becomes significantly more intricate for signed double stars. We obtain a characterization of…

Combinatorics · Mathematics 2026-04-24 Brian DSouza , Jessica Pereira

For signed graphs we provide a cubic polynomial upper bound on the multiplicity of its eigenvalues. We show that this bound is sharp by providing examples of signed graphs in which it is attained. We also discuss particular cases in which…

Combinatorics · Mathematics 2019-11-05 Farzaneh Ramezani , Peter Rowlinson , Zoran Stanic

The mutually enriching relationship between graphs and matroids has motivated discoveries in both fields. In this paper, we exploit the similar relationship between embedded graphs and delta-matroids. There are well-known connections…

Combinatorics · Mathematics 2019-03-04 Carolyn Chun , Iain Moffatt , Steven D. Noble , Ralf Rueckriemen

We extend to infinite graphs the matroidal characterization of finite graph duality, that two graphs are dual iff they have complementary spanning trees in some common edge set. The naive infinite analogue of this fails. The key in an…

Combinatorics · Mathematics 2011-06-08 Reinhard Diestel , Julian Pott

A signed graph is a graph in which each edge is labeled with $+1$ or $-1$. A (proper) vertex coloring of a signed graph is a mapping $\f$ that assigns to each vertex $v\in V(G)$ a color $\f(v)\in \mz$ such that every edge $vw$ of $G$…

Combinatorics · Mathematics 2015-07-17 Thomas Schweser , Michael Stiebitz

A signed graph is a pair $(G,\Sigma)$, where $G=(V,E)$ is a graph (in which parallel edges are permitted, but loops are not) with $V=\{1,\ldots,n\}$ and $\Sigma\subseteq E$. The edges in $\Sigma$ are called odd and the other edges of $E$…

Combinatorics · Mathematics 2020-02-24 Marina Arav , Frank J. Hall , Zhongshan Li , Hein van der Holst

A signed graph is a graph with edges marked positive and negative; it is unbalanced if some cycle has negative sign product. We introduce the concept of vector valued switching function in signed graphs, which extends the concept of…

Combinatorics · Mathematics 2023-05-23 Shahul Hameed K , Albin Mathew , Germina K A , Thomas Zaslavsky

An arithmetical structure on a graph is given by a labeling of the vertices which satisfies certain divisibility properties. In this note, we look at several families of graphs and attempt to give counts on the number of arithmetical…

Combinatorics · Mathematics 2019-03-05 Darren Glass , Joshua Wagner

We study the balance of $G$-gain graphs, where $G$ is an arbitrary group, by investigating their adjacency matrices and their spectra. As a first step, we characterize switching equivalence and balance of gain graphs in terms of their…

Combinatorics · Mathematics 2021-07-27 Matteo Cavaleri , Daniele D'Angeli , Alfredo Donno

For a graph with edge ordering, a linear order on the edge set, we obtain a permutation of vertices by considering the edges as transpositions of endvertices. It is known from D\'enes' results that the permutation of a tree is a full cyclic…

Combinatorics · Mathematics 2023-05-31 Ryo Uchiumi

An excluded minor characterization for the class of binary signed-graphic matroids with graphic cocircuits is provided. In this report we present the necessary computations for the case analysis in the proof.

Combinatorics · Mathematics 2012-05-07 Konstantinos Papalamprou , Leonidas Pitsoulis

A $\mathbb{T}$-gain graph is a simple graph in which a unit complex number is assigned to each orientation of an edge, and its inverse is assigned to the opposite orientation. The associated adjacency matrix is defined canonically, and is…

Combinatorics · Mathematics 2023-04-18 Aniruddha Samanta , M. Rajesh Kannan

A complex unit gain graph ($ \mathbb{T} $-gain graph), $ \Phi=(G, \varphi) $ is a graph where the gain function $ \varphi $ assigns a unit complex number to each orientation of an edge of $ G $ and its inverse is assigned to the opposite…

Combinatorics · Mathematics 2023-12-29 Aniruddha Samanta , M. Rajesh Kannan

We define the Sign Game as a two-player game played on a simple undirected mathematical graph $G$. The players alternate turns, assigning vertices of $G$ either $1$ or $-1$, and edges take on the value of the product of their endvertices.…

Combinatorics · Mathematics 2025-11-12 Liz Blum , Lily Brustkern , Rosetta Hawkins , Neil R. Nicholson , Ranjan Rohatgi

In this paper, we analyze embeddings of grid graphs on orientable surfaces. We determine the genus of a large class of k-dimensional grid graphs and effective two-sided bounds for the genus of any 3-dimensional grid graph, both in terms of…

Combinatorics · Mathematics 2022-04-20 Christian Millichap , Fabian Salinas

In this paper, we study the signed domination numbers of graphs and present new sharp lower and upper bounds for this parameter. As an example, we present a lower bound on signed domination number of trees in terms of the order, leaves and…

Combinatorics · Mathematics 2019-08-27 S. M. Hosseini Moghaddam , Abdollah Khodkar , Babak Samadi

In fields ranging from business to systems biology, directed graphs with edges labeled by signs are used to model systems in a simple way: the nodes represent entities of some sort, and an edge indicates that one entity directly affects…

Category Theory · Mathematics 2026-03-20 John C. Baez , Adittya Chaudhuri

There is a well-known way to describe a link diagram as a (signed) plane graph, called its Tait graph. This concept was recently extended, providing a way to associate a set of embedded graphs (or ribbon graphs) to a link diagram. While…

Combinatorics · Mathematics 2014-10-01 Iain Moffatt
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