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Related papers: Cliques and the Spectral Radius

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The bandwidth of a graph G is the minimum of the maximum difference between adjacent labels when the vertices have distinct integer labels. We provide a polynomial algorithm to produce an optimal bandwidth labeling for graphs in a special…

Combinatorics · Mathematics 2007-05-23 Le Tu Quoc Hung , Maciej M. Syslo , Margaret L. Weaver , Douglas B. West

Shiu, Chan and Chang [On the spectral radius of graphs with connectivity at most $k$, J. Math. Chem., 46 (2009), 340-346] studied the spectral radius of graphs of order $n$ with $\kappa(G) \leq k$ and showed that among those graphs, the…

Combinatorics · Mathematics 2011-07-28 Hongliang Lu , Yuqing Lin

We determine the maximum possible number of edges of a graph with $n$ vertices, matching number at most $s$ and clique number at most $k$ for all admissible values of the parameters.

Combinatorics · Mathematics 2022-10-28 Noga Alon , Peter Frankl

We give upper and lower bounds for the spectral radius of a nonnegative matrix by using its average 2-row sums, and characterize the equality cases if the matrix is irreducible. We also apply these bounds to various nonnegative matrices…

Combinatorics · Mathematics 2014-05-30 Rundan Xing , Bo Zhou

Let $G$ be a simple connected undirected graph. The Laplacian spectral ratio of $G$, denoted by $R_L(G)$, is defined as the quotient between the largest and second smallest Laplacian eigenvalues of $G$, which is closely related to the…

Combinatorics · Mathematics 2023-02-22 Zhen Lin , Jiajia Wang , Min Cai

Hypergraphs are a generalization of graphs in which edges can connect any number of vertices. They allow the modeling of complex networks with higher-order interactions, and their spectral theory studies the qualitative properties that can…

Combinatorics · Mathematics 2021-12-01 Raffaella Mulas

We study the spectral statistics of quantum (metric) graphs whose vertices are equipped with preferred orientation vertex conditions. When comparing their spectral statistics to those predicted by suitable random matrix theory ensembles,…

Spectral Theory · Mathematics 2025-08-08 Ram Band , Pavel Exner , Divya Goel , Aviya Strauss

We study some spectral properties of a matrix that is constructed as a combination of a Laplacian and an adjacency matrix of simple graphs. The matrix considered depends on a positive parameter, as such we consider the implications in…

Dynamical Systems · Mathematics 2024-08-02 Riccardo Bonetto , Hildeberto Jardón Kojakhmetov

Let $G = (V,E)$ be an $n$-vertex graph and let $c: E \to \mathbb{N}$ be a coloring of its edges. Let $d^c(v)$ be the number of distinct colors on the edges at $v \in V$ and let $\delta^c(G) = \min_{v \in V} \{ d^{c}(v) \}$. H. Li proved…

Combinatorics · Mathematics 2024-07-12 Andrzej Czygrinow , Theodore Molla , Brendan Nagle

Motivated by an approach to visualization of high dimensional statistical data given in Hurley and Oldford (2011), this work examines the clique structure of $J_n(m, m-1)$ Johnson graphs. Cliques and maximal cliques are characterized and…

Combinatorics · Mathematics 2022-08-29 Pavel Shuldiner , R. Wayne Oldford

We introduce a quantitative measure of network bipartivity as a proportion of even to total number of closed walks in the network. Spectral graph theory is used to quantify how close to bipartite a network is and the extent to which…

Statistical Mechanics · Physics 2009-11-11 Ernesto Estrada , Juan A. Rodriguez-Velazquez

For a nonnegative integer $k$, a graph $G$ is said to be $k$-factor-critical if $G-Q$ admits a perfect matching for any $Q\subseteq V(G)$ with $|Q|=k$. In this article, we prove spectral radius conditions for the existence of…

Combinatorics · Mathematics 2024-01-30 Sizhong Zhou , Zhiren Sun , Yuli Zhang

We present the Boolean dimension of a graph, we relate it with the notions of inner, geometric and symplectic dimensions, and with the rank and minrank of a graph. We obtain an exact formula for the Boolean dimension of a tree in terms of a…

Combinatorics · Mathematics 2022-09-07 Maurice Pouzet , Hamza Si Kaddour , Bhalchandra D. Thatte

We determine the digraphs which achieve the second, the third and the fourth minimum spectral radii respectively among strongly connected digraphs of order $n\ge 4$, and thus we answer affirmatively the problem whether the unique digraph…

Combinatorics · Mathematics 2013-05-02 Jianping Li , Bo Zhou

Counts of small subgraphs, or graphlet counts, are widely applicable to measure graph similarity. Computing graphlet counts can be computationally expensive and may pose obstacles in network analysis. We study the role of cliques in…

Social and Information Networks · Computer Science 2024-01-09 Anthony Bonato , Zhiyuan Zhang

We propose a general approach to the description of spectra of complex networks. For the spectra of networks with uncorrelated vertices (and a local tree-like structure), exact equations are derived. These equations are generalized to the…

Statistical Mechanics · Physics 2009-11-10 S. N. Dorogovtsev , A. V. Goltsev , J. F. F. Mendes , A. N. Samukhin

We investigate clique trees of infinite locally finite chordal graphs. Our main contribution is a bijection between the set of clique trees and the product of local finite families of finite trees. Even more, the edges of a clique tree are…

Combinatorics · Mathematics 2018-03-23 Christoph Hofer-Temmel , Florian Lehner

The generalized distance spectral radius of a connected graph $G$ is the spectral radius of the generalized distance matrix of $G$, defined by $$D_\alpha(G)=\alpha Tr(G)+(1-\alpha)D(G), \;\;0\le\alpha \le 1,$$ where $D(G)$ and $Tr(G)$…

Combinatorics · Mathematics 2019-01-24 Shu-Yu Cui , Gui-Xian Tian , Lu Zheng

In this paper, we investigate some relations between the invariants (including vertex and edge connectivity and forwarding indices) of a graph and its Laplacian eigenvalues. In addition, we present a sufficient condition for the existence…

Combinatorics · Mathematics 2014-07-23 Rong-Ying Pan , Jing Yan , Xiao-Dong Zhang

Bessel multipliers are operators defined from two Bessel sequences of elements of a Hilbert space and a complex sequence, and have frame multipliers as particular cases. In this paper an estimate of the spectral radius of a Bessel…

Functional Analysis · Mathematics 2023-10-31 Rosario Corso
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