Results 61 to 70 of about 1,618,968 (159)
A Note on Some Bounds of the α‐Estrada Index of Graphs
Advances in Mathematical Physics, Volume 2020, Issue 1, 2020., 2020 Let G be a simple graph with n vertices. Let A~αG=αDG+1−αAG, where 0 ≤ α ≤ 1 and A(G) and D(G) denote the adjacency matrix and degree matrix of G, respectively. EEαG=∑i=1neλi is called the α‐Estrada index of G, where λ1, ⋯, λn denote the eigenvalues of A~αG. In this paper, the upper and lower bounds for EEα(G) are given.
Yang Yang +3 more
wiley +1 more source
Spectra of Graphs Resulting from Various Graph Operations and Products: a Survey
Special Matrices, 2018 Let G be a graph on n vertices and A(G), L(G), and |L|(G) be the adjacency matrix, Laplacian matrix and signless Laplacian matrix of G, respectively. The paper is essentially a survey of known results about the spectra of the adjacency, Laplacian and ...
Barik S., Kalita D., Pati S., Sahoo G.
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The maximum clique and the signless Laplacian eigenvalues [PDF]
, 1994 summary:Lower and upper bounds are obtained for the clique number $\omega (G)$ and the independence number $\alpha (G)$, in terms of the eigenvalues of the signless Laplacian matrix of a graph $G$
Liu, BoLian +3 more
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The sun graph is determined by its signless Laplacian spectrum [PDF]
, 2010 For a simple undirected graph G, the corresponding signless Laplacian matrix is defined as D(G) + A(G) in which D(G) and A(G) are degree matrix and adjacency matrix of G, respectively.
Mirzakhah, Maryam, Kiani, Dariush
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On graphs with adjacency and signless Laplacian matrices eigenvectors entries in {−1,+1}
Linear Algebra and its Applications, 2021 Let $G$ be a simple graph. In 1986, Herbert Wilf asked what kind of graphs have an eigenvector with entries formed only by $\pm 1$? In this paper, we answer this question for the adjacency, Laplacian and signless Laplacian matrix of a graph. Besides, we generalize the concept of an exact graph to the adjacency and signless Laplacian matrices.
Jorge Alencar, Leonardo de Lima
openaire +3 more sources
Bounding the sum of the largest signless Laplacian eigenvalues of a graph [PDF]
, 2022 We show several sharp upper and lower bounds for the sum of the largest eigenvalues of the signless Laplacian matrix. These bounds improve and extend previously known bounds.Comment: arXiv admin note: text overlap with arXiv:1412 ...
Mohammadi, Mona +11 more
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Color laplacian and color signless laplacian energy of complement of subgroup graph of dihedral group [PDF]
, 2020 Laplacian and signless laplacian energy of a finite graph is the most interesting topics on areas of energy of a graph. The new concept of energy of a graph is color energy and furthermore color laplacian and color signless laplacian energy.
Mohammad Jauhari +7 more
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On the sum of signless Laplacian spectra of graphs
Karpatsʹkì Matematičnì Publìkacìï, 2019 For a simple graph $G(V,E)$ with $n$ vertices, $m$ edges, vertex set $V(G)=\{v_1, v_2, \dots, v_n\}$ and edge set $E(G)=\{e_1, e_2,\dots, e_m\}$, the adjacency matrix $A=(a_{ij})$ of $G$ is a $(0, 1)$-square matrix of order $n$ whose $(i,j)$-entry is ...
S. Pirzada, H.A. Ganie, A.M. Alghamdi
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On the signless Laplacian and normalized signless Laplacian spreads of graphs
, 2022 Let G = (V, E), V = {v1, v2, …, vn}, be a simple connected graph with n vertices, m edges and a sequence of vertex degrees d1 ≽ d2 ≽ … ≽ dn. Denote by A and D the adjacency matrix and diagonal vertex degree matrix of G, respectively.
Igor Milovanović +8 more
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On Some Properties of Characteristics Polynomials of the Complete Graphs Kn [PDF]
Engineering and Technology Journal, 2013 This paper discusses the properties of the characteristic polynomial of the complete graphs Kn, n=1, 2… respective to the adjacency matrices. Two different types of matrices, the adjacency matrix and the signless Laplacian matrix, are presented.
Nuha A. Rajab +2 more
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