Results 41 to 50 of about 272 (159)
On the Distance Spectral Radius of Trees with Given Degree Sequence
Discussiones Mathematicae Graph Theory, 2020 We consider the problem of maximizing the distance spectral radius and a slight generalization thereof among all trees with some prescribed degree sequence.
Dadedzi Kenneth +2 more
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A Lower Bound for the Spectral Radius of Graphs with Fixed Diameter [PDF]
, 2008 AMS classifications: 05C50 ...
Koolen, J.H. +3 more
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On the Displacement of Eigenvalues When Removing a Twin Vertex
Discussiones Mathematicae Graph Theory, 2020 Twin vertices of a graph have the same open neighbourhood. If they are not adjacent, then they are called duplicates and contribute the eigenvalue zero to the adjacency matrix.
Briffa Johann A., Sciriha Irene
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The Number of P-Vertices of Singular Acyclic Matrices: An Inverse Problem
Discussiones Mathematicae Graph Theory, 2020 Let A be a real symmetric matrix. If after we delete a row and a column of the same index, the nullity increases by one, we call that index a P-vertex of A.
Du Zhibin, da Fonseca Carlos M.
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Eigenvalue bracketing for discrete and metric graphs [PDF]
, 2008 28 pages, 6 figures.-- MSC2000 codes: 05C50, 05C70, 47A10.-- ArXiv pre-print available at: http://arxiv.org/abs/0804.1076MR#: MR2446037 (2010a:47076)Zbl#: Zbl 1152.05044We develop eigenvalue estimates for the Laplacians on discrete and metric graphs ...
Post, Olaf +4 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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Bounds on F-index of tricyclic graphs with fixed pendant vertices
Open Mathematics, 2020 The F-index F(G) of a graph G is obtained by the sum of cubes of the degrees of all the vertices in G. It is defined in the same paper of 1972 where the first and second Zagreb indices are introduced to study the structure-dependency of total π-electron ...
Akram Sana +2 more
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Uniformity in Association schemes and Coherent Configurations: Cometric Q-Antipodal Schemes and Linked Systems [PDF]
, 2010 2010 Mathematics Subject Classification.
Edwin R. Van Dam +5 more
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Eccentricity energy change of complete multipartite graphs due to edge deletion
Special Matrices, 2022 The eccentricity matrix ɛ(G) of a graph G is obtained from the distance matrix of G by retaining the largest distances in each row and each column, and leaving zeros in the remaining ones. The eccentricity energy of G is sum of the absolute values of the
Mahato Iswar, Kannan M. Rajesh
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Perturbations in a Signed Graph and its Index
Discussiones Mathematicae Graph Theory, 2018 In this paper we consider the behaviour of the largest eigenvalue (also called the index) of signed graphs under small perturbations like adding a vertex, adding an edge or changing the sign of an edge.
Stanić Zoran
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