Results 31 to 40 of about 254 (116)
Bounds on the Spectral Radius of a Nonnegative Matrix and Its Applications
Journal of Applied Mathematics, Volume 2016, Issue 1, 2016., 2016 We obtain the sharp bounds for the spectral radius of a nonnegative matrix and then obtain some known results or new results by applying these bounds to a graph or a digraph and revise and improve two known results.
Danping Huang, Lihua You, Ali R. Ashrafi
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The Minimum Spectral Radius of Signless Laplacian of Graphs with a Given Clique Number
Discussiones Mathematicae Graph Theory, 2014 In this paper we observe that the minimal signless Laplacian spectral radius is obtained uniquely at the kite graph PKn−ω,ω among all connected graphs with n vertices and clique number ω.
Su Li, Li Hong-Hai, Zhang Jing
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The Least Algebraic Connectivity of Graphs
Discrete Dynamics in Nature and Society, Volume 2015, Issue 1, 2015., 2015 The algebraic connectivity of a graph is defined as the second smallest eigenvalue of the Laplacian matrix of the graph, which is a parameter to measure how well a graph is connected. In this paper, we present two unique graphs whose algebraic connectivity attain the minimum among all graphs whose complements are trees, but not stars, and among all ...
Guisheng Jiang +3 more
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Spectral Radius and Hamiltonicity of Graphs
Discussiones Mathematicae Graph Theory, 2019 In this paper, we study the Hamiltonicity of graphs with large minimum degree. Firstly, we present some conditions for a simple graph to be Hamilton-connected and traceable from every vertex in terms of the spectral radius of the graph or its complement,
Yu Guidong +3 more
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On the Aα-Spectral Radii of Cactus Graphs
Mathematics, 2020 Let A ( G ) be the adjacent matrix and D ( G ) the diagonal matrix of the degrees of a graph G, respectively. For 0 ≤ α ≤ 1 , the A α -matrix is the general adjacency and signless Laplacian spectral matrix having the form of
Chunxiang Wang +3 more
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k路覆盖图的新充分条件(New sufficient conditions on k -path-coverable graphs)
Zhejiang Daxue xuebao. Lixue ban, 2019 Let G be a simple connected graph of order n. A graph G is k-path-coverable if its vertex set V ( G ) can be covered by kor fewer vertex-disjoint paths. In this paper, we give some new sufficient conditions for a graph to be k-path-coverable in terms of ...
JIAHuicai(贾会才)
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Energy Conditions for Hamiltonicity of Graphs
Discrete Dynamics in Nature and Society, Volume 2014, Issue 1, 2014., 2014 Let G be an undirected simple graph of order n. Let A(G) be the adjacency matrix of G, and let μ1(G) ≤ μ2(G)≤⋯≤μn(G) be its eigenvalues. The energy of G is defined as ℰ(G)=∑i=1n |μi(G)|. Denote by GBPT a bipartite graph. In this paper, we establish the sufficient conditions for G having a Hamiltonian path or cycle or to be Hamilton‐connected in terms ...
Guidong Yu +4 more
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The Largest Laplacian Spectral Radius of Unicyclic Graphs with Fixed Diameter
Journal of Applied Mathematics, Volume 2013, Issue 1, 2013., 2013 We identify graphs with the maximal Laplacian spectral radius among all unicyclic graphs with n vertices and diameter d.
Haixia Zhang, Baolin Wang
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Some Results on the Signless Laplacian Spectra of Unicyclic Graphs
International Scholarly Research Notices, Volume 2011, Issue 1, 2011., 2011 We determine the second to fourth largest (resp. the second smallest) signless Laplacian spectral radii and the second to fourth largest signless Laplacian spreads together with the corresponding graphs in the class of unicyclic graphs with n vertices.
Muhuo Liu, M. Asaad, P. Koshlukov
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The Aα-Spectral Radii of Graphs with Given Connectivity
Mathematics, 2019 The A α -matrix is A α ( G ) = α D ( G ) + ( 1 − α ) A ( G ) with α ∈ [ 0 , 1 ] , given by Nikiforov in 2017, where A ( G ) is adjacent matrix, and D ( G ) is its ...
Chunxiang Wang, Shaohui Wang
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