Results 21 to 30 of about 960 (155)
The spectral radius of signless Laplacian matrix and sum-connectivity index of graphs
AKCE International Journal of Graphs and Combinatorics, 2022 The sum-connectivity index of a graph G is defined as the sum of weights [Formula: see text] over all edges uv of G, where du and dv are the degrees of the vertices u and v in G, respectively.
A. Jahanbani, S. M. Sheikholeslami
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TWO SHARP UPPER BOUNDS FOR THE SIGNLESS LAPLACIAN SPECTRAL RADIUS OF GRAPHS [PDF]
Discrete Mathematics, Algorithms and Applications, 2011 The signless Laplacian matrix of a graph is the sum of its degree diagonal and adjacency matrices. In this paper, we present a sharp upper bound for the spectral radius of the adjacency matrix of a graph. Then this result and other known results are used to obtain two new sharp upper bounds for the signless Laplacian spectral radius.
Chen, Ya-Hong +2 more
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Discrete Applied Mathematics, 2017 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Xi, Weige, Wang, Ligong
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Signless Laplacian spectral radius and Hamiltonicity
Linear Algebra and its Applications, 2010 For an \(n\) vertex of a graph \(G\), the matrix \(L^*(G)=D(G)+A(G)\) is the signless Laplacian matrix of \(G\), where \(D(G)\) is the diagonal matrix of vertex degrees and \(A(G)\) is the adjacency matrix of \(G\). Let \(\gamma(G)\) be the largest eigenvalue of \(L^*(G)\).
Bo Zhou
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Domination number and (signless Laplacian) spectral radius of cactus graphs
The Electronic Journal of Linear AlgebraA cactus graph is a connected graph whose block is either an edge or a cycle. A vertex set $S\subseteq V(G)$ is said to be a dominating set of a graph $G$ if every vertex in $V(G)\setminus S$ is adjacent to a vertex in $S$. There are several results on the (signless Laplacian) spectral radius and domination number in graph theory.
Ye Cui, Yuanyuan Chen, Dan Li, Yue Zhang
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Sharp Upper Bounds on the Signless Laplacian Spectral Radius of Strongly Connected Digraphs
Discussiones Mathematicae Graph Theory, 2016 Let G = (V (G),E(G)) be a simple strongly connected digraph and q(G) be the signless Laplacian spectral radius of G. For any vertex vi ∈ V (G), let d+i denote the outdegree of vi, m+i denote the average 2-outdegree of vi, and N+i denote the set of out ...
Xi Weige, Wang Ligong
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Spanning trees and signless Laplacian spectral radius in graphs [PDF]
12 ...
Sufang Wang, Wei Zhang
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The signless Laplacian spectral radius of subgraphs of regular graphs [PDF]
, 2016 Let $q(H)$ be the signless Laplacian spectral radius of a graph $H$. In this paper, we prove that \\1. Let $H$ be a proper subgraph of a $ $-regular graph $G$ with $n$ vertices and diameter $D$. Then $$2 - q(H)>\frac{1}{n(D-\frac{1}{4})}.$$ \\2. Let $H$ be a proper subgraph of a $k$-connected $ $-regular graph $G$ with $n$ vertices, where $k\geq ...
Qi Kong, Ligong Wang
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The (signless Laplacian) spectral radius (of subgraphs) of uniform hypergraphs
Filomat, 2019 Let ?1(G) and q1(G) be the spectral radius and the signless Laplacian spectral radius of a kuniform hypergraph G, respectively. In this paper, we give the lower bounds of d-?1(H) and 2d-q1(H), where H is a proper subgraph of a f (-edge)-connected d-regular (linear) k-uniform hypergraph.
Cunxiang Duan +3 more
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The smallest spectral radius of graphs with a given clique number. [PDF]
ScientificWorldJournal, 2014 The first four smallest values of the spectral radius among all connected graphs with maximum clique size ω ≥ 2 are obtained.
Zhang JM, Huang TZ, Guo JM.
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