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Related papers: On the Powers of Signed Graphs

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Graphs provide a powerful representation formalism that offers great promise to benefit tasks like handwritten signature verification. While most state-of-the-art approaches to signature verification rely on fixed-size representations,…

Computer Vision and Pattern Recognition · Computer Science 2019-06-26 Paul Maergner , Nicholas R. Howe , Kaspar Riesen , Rolf Ingold , Andreas Fischer

Let $G$ be a graph. For a subset $X$ of $V(G)$, the switching $\sigma$ of $G$ is the signed graph $G^{\sigma}$ obtained from $G$ by reversing the signs of all edges between $X$ and $V(G)\setminus X$. Let $A(G^{\sigma})$ be the adjacency…

Combinatorics · Mathematics 2021-08-23 Zhenan Shao , Xiying Yuan

A \textit{signed graph} is a simple graph whose edges are labelled with positive or negative signs. A cycle is \textit{positive} if the product of its edge signs is positive. A signed graph is \textit{balanced} if every cycle in the graph…

Combinatorics · Mathematics 2021-10-12 Deepak Sehrawat , Bikash Bhattacharjya

The graph $G$ is said to be strongly regular with parameters $(n,k,\lambda,\mu)$ if the following conditions hold: (1) each vertex has $k$ neighbours; (2) any two adjacent vertices of $G$ have $\lambda$ common neighbours; (3) any two…

Combinatorics · Mathematics 2021-10-06 Jeepamol J Palathingal , Aparna Lakshmanan S , Greg Markowsky

A 2-edge-colored graph or a signed graph is a simple graph with two types of edges. A homomorphism from a 2-edge-colored graph $G$ to a 2-edge-colored graph $H$ is a mapping $\varphi: V(G) \rightarrow V(H)$ that maps every edge in $G$ to an…

Combinatorics · Mathematics 2020-09-14 Christopher Duffy , Fabien Jacques , Mickael Montassier , Alexandre Pinlou

These notes concern aspects of various graphs whose vertex set is a group $G$ and whose edges reflect group structure in some way (so that they are invariant under the action of the automorphism group of $G$). The graphs I will discuss are…

Group Theory · Mathematics 2021-03-29 Peter J. Cameron

The study on parity signed graphs was initiated by Acharya and Kureethara very recently and then followed by Zaslavsky etc.. Let $(G,\sigma)$ be a signed graph on $n$ vertices. If $(G,\sigma)$ is switch-equivalent to $(G,+)$ at a set of…

Combinatorics · Mathematics 2021-11-10 Ligang Jin , Xiaoyue Chen , Yingli Kang

A graph $G$ has the $k$-strong parity property if for any $X\subseteq V(G)$ with $|X|$ even, $G$ contains a spanning subgraph $F$ with $d_F(u)\equiv1$ (mod 2) for each $u\in X$ and $d_F(v)\in\{k,k+2,k+4,\ldots\}$ for each $v\in…

Combinatorics · Mathematics 2025-05-28 Jie Wu

A divisor graph $G$ is an ordered pair $(V, E)$ where $V \subset \mathbbm{Z}$ and for all $u \neq v \in V$, $u v \in E$ if and only if $u \mid v$ or $v \mid u$. A graph which is isomorphic to a divisor graph is also called a divisor graph.…

Combinatorics · Mathematics 2007-05-23 Le Anh Vinh

Graphs can have different properties that lead to several graph types and may allow for a varying representation of diverse information. In order to clarify the modeling power of graphs, we introduce a partial order on the most common graph…

Discrete Mathematics · Computer Science 2022-09-08 Josephine M. Thomas , Silvia Beddar-Wiesing , Alice Moallemy-Oureh , Rüdiger Nather

Let $D$ be a weighted oriented graph and $I(D)$ be its edge ideal. If $D$ contains an induced odd cycle of length $2n+1$, under certain condition we show that $ {I(D)}^{(n+1)} \neq {I(D)}^{n+1}$. We give necessary and sufficient condition…

Commutative Algebra · Mathematics 2022-04-12 Mousumi Mandal , Dipak Kumar Pradhan

The symmetric tensor power of graphs is introduced and its fundamental properties are explored. A wide range of intriguing phenomena occur when one considers symmetric tensor powers of familiar graphs. A host of open questions are…

We consider the notion of a signed magic array, which is an $m \times n$ rectangular array with the same number of filled cells $s$ in each row and the same number of filled cells $t$ in each column, filled with a certain set of numbers…

Combinatorics · Mathematics 2017-01-09 Abdollah Khodkar , Christian Schulz , Nathan Wagner

We generalise to signed graphs a classical result of Tutte [Canad. J. Math. 8 (1956), 13--28] stating that every integer flow can be expressed as a sum of characteristic flows of circuits. In our generalisation, the r\^ole of circuits is…

Combinatorics · Mathematics 2014-07-22 Edita Macajova , Martin Skoviera

Signed graphs have their edges labeled either as positive or negative. $\rho(M)$ denote the $M$-spectral radius of $\Sigma$, where $M=M(\Sigma)$ is a real symmetric graph matrix of $\Sigma$. Obviously,…

Combinatorics · Mathematics 2022-01-19 Dan Li , Huiqiu Lin , Jixiang Meng

In this work, we discuss some properties of the eigenvalues of some classes of signed complete graphs. We also obtain the form of characteristic polynomial for these graphs.

Combinatorics · Mathematics 2023-09-12 Prajnanaswaroopa S

Unigraphs are graphs uniquely determined by their own degree sequence up to isomorphism. There are many subclasses of unigraphs such as threshold graphs, split matrogenic graphs, matroidal graphs, and matrogenic graphs. Unigraphs and these…

Data Structures and Algorithms · Computer Science 2019-04-23 Takashi Horiyama , Jun Kawahara , Shin-ichi Minato , Yu Nakahata

For a graph $G$ and a non-zero real number $\alpha$, the graph invariant $S_{\alpha}(G)$ is the sum of the $\alpha^{th}$ power of the non-zero signless Laplacian eigenvalues of $G$. In this paper, we obtain the sharp bounds of…

Combinatorics · Mathematics 2013-06-07 Lihua You , Jieshan Yang

Let $G$ be a finite group and $\sigma$ a partition of the set of all? primes $\Bbb{P}$, that is, $\sigma =\{\sigma_i \mid i\in I \}$, where $\Bbb{P}=\bigcup_{i\in I} \sigma_i$ and $\sigma_i\cap \sigma_j= \emptyset $ for all $i\ne j$. If $n$…

Group Theory · Mathematics 2020-01-27 Alexander N. Skiba

A seminal result by Whitney describes when two graphs have the same cycles. We consider the analogous problem for even cycle matroids. A representation of an even cycle matroid is a pair formed by a graph together with a special set of…

Combinatorics · Mathematics 2011-09-15 Bertrand Guenin , Irene Pivotto , Paul Wollan