English
Related papers

Related papers: Graph Energies of Generalized and Shadow-Splitting…

200 papers

Equitable list arboricity, introduced by Zhang in 2016, generalizes the notion of equitable list coloring by requiring the subgraph induced by each color class to be acyclic (instead of edgeless) in addition to the usual upper bound on the…

Combinatorics · Mathematics 2021-06-03 Hemanshu Kaul , Jeffrey A. Mudrock , Michael J. Pelsmajer

Motivated by the linear time algorithm that locates the eigenvalues of a cograph G [10], we investigate the multiplicity of eigenvalue for \lambda \neq -1,0. For cographs with balanced cotrees we determine explicitly the highest value for…

Combinatorics · Mathematics 2018-01-30 Luiz Emilio Allem , Fernando Tura

Let $\Gamma$ be a graph with the adjacency matrix $A$. The energy of $\Gamma$ is the sum of the absolute values of the eigenvalues of $A$. In this article we compute the energies of the commuting graphs of some finite groups and discuss…

Combinatorics · Mathematics 2019-04-30 Reza Sharafdini , Rajat Kanti Nath , Rezvan Darbandi

Considering a graph $H$ of order $p$, a generalized $H$-join operation of a family of graphs $G_1,..., G_p$, constrained by a family of vertex subsets $S_i \subseteq V(G_i)$, $i=1,..., p,$ is introduced. When each vertex subset $S_i$ is…

Combinatorics · Mathematics 2012-05-09 Domingos M. Cardoso , Enide A. Martins , Maria Robbiano , Oscar Rojo

In this paper, we compute common neighbourhood Laplacian spectrum, common neighbourhood signless Laplacian spectrum and their respective energies of commuting graph of some finite non-abelian groups including some AC-groups, groups whose…

Group Theory · Mathematics 2024-03-05 Firdous Ee Jannat , Rajat Kanti Nath

The energy of a graph is defined as the sum of the absolute values of the eigenvalues of the graph. In this paper, we present a new method to compare the energies of two $k$-subdivision bipartite graphs on some cut edges. As the…

Combinatorics · Mathematics 2011-11-10 Hai-Ying Shan , Jia-Yu Shao , Li Zhang , Chang-Xiang He

In this article we construct a series of new infinite families of strongly regular graphs with the same parameters as the point-graphs of non-singular quadrics in PG(n,2).

Combinatorics · Mathematics 2016-06-20 S. G. Barwick , Wen-Ai Jackson , Tim Penttila

Let $G$ be a graph of order $n$ with adjacency matrix $A(G)$. The \textit{energy} of graph $G$, denoted by $\mathcal{E}(G)$, is defined as the sum of absolute value of eigenvalues of $A(G)$. It was conjectured that if $A(G)$ is…

Combinatorics · Mathematics 2022-07-12 Saieed Akbari , Hossein Dabirian , S. Mahmood Ghasemi

In this paper we study the class of graphs $G_{m,n}$ that have the same degree sequence as two disjoint cliques $K_m$ and $K_n$, as well as the class $\overline G_{m,n}$ of the complements of such graphs. We establish various properties of…

Combinatorics · Mathematics 2023-08-15 Boris Brimkov , Valentin Brimkov

The energy of a graph $G$, denoted by $E(G)$, is defined as the sum of the absolute values of all eigenvalues of $G$. Let $G$ be a graph of order $n$ and ${\rm rank}(G)$ be the rank of the adjacency matrix of $G$. In this paper we…

Combinatorics · Mathematics 2007-09-21 S. Akbari , E. Ghorbani , S. Zare

Graphs may be used to represent many different problem domains -- a concrete example is that of detecting communities in social networks, which are represented as graphs. With big data and more sophisticated applications becoming widespread…

Distributed, Parallel, and Cluster Computing · Computer Science 2017-04-03 Miguel E. Coimbra , Alexandre P. Francisco , Luis Veiga

The total graph of $G$, $\mathcal T(G)$ is the graph whose set of vertices is the union of the sets of vertices and edges of $G$, where two vertices are adjacent if and only if they stand for either incident or adjacent elements in $G$. Let…

Spectral Theory · Mathematics 2018-06-13 Eber Lenes , Exequiel Mallea-Zepeda , María Robbiano , Jonnathan Rodríguez

The sum of the absolute values of the eigenvalues of a graph is called the energy of the graph. We study the problem of finding graphs with extremal energy within specified classes of graphs. We develop tools for treating such problems and…

Combinatorics · Mathematics 2007-10-31 Dragos Cvetkovic , Jason Grout

This is an introduction to graph theory, from a geometric and analytic viewpoint. A finite graph $X$ is described by its adjacency matrix $d\in M_N(0,1)$, which can be thought of as being a kind of discrete Laplacian, and we first discuss…

Quantum Algebra · Mathematics 2024-10-23 Teo Banica

In this paper, we define and obtain several properties of the (adjacency) energy of a hypergraph. In particular, bounds for this energy are obtained as functions of structural and spectral parameters, such as Zagreb index and spectral…

Combinatorics · Mathematics 2021-06-15 Kauê Cardoso , Renata Del-Vecchio , Lucas Portugal , Vilmar Trevisan

This is a chapter in a forthcoming book on completely regular codes in distance regular graphs. The chapter provides an overview, and some original results, on codes in distance regular graphs which admit symmetries via a permutation group…

Combinatorics · Mathematics 2024-07-16 Daniel R. Hawtin , Cheryl E. Praeger

We generalize the concept of token graphs to obtain supertoken graphs. In the latter case, there can be more than one token in a vertex. We formally define supertoken graphs and establish their basic properties. Moreover, we provide some…

Combinatorics · Mathematics 2026-04-08 Mónica A. Reyes , Cristina Dalfó , Miquel Àngel Fiol

We study the connectivity of proper power graphs of some family of finite groups including nilpotent groups, groups with a non-trivial partition, and symmetric and alternating groups.

Group Theory · Mathematics 2014-01-28 Alireza Doostabadi , Mohammad Farrokhi Derakhshandeh Ghouchan

We introduce Graph Hopfield Networks, whose energy function couples associative memory retrieval with graph Laplacian smoothing for node classification. Gradient descent on this joint energy yields an iterative update interleaving Hopfield…

Machine Learning · Computer Science 2026-03-05 Abinav Rao , Alex Wa , Rishi Athavale

We prove that, for any graph $G$, its graph energy is at least twice the Randic index. We show that equality holds if and only if $G$ is the union of complete bipartite graphs.

Combinatorics · Mathematics 2020-09-18 Gerardo Arizmendi , Octavio Arizmendi