Results 21 to 30 of about 2,691 (126)
Computing Laplacian energy, Laplacian-energy-like invariant and Kirchhoff index of graphs
Acta Universitatis Sapientiae: Informatica, 2022 Let G be a simple connected graph of order n and size m. The matrix L(G)= D(G)− A(G) is called the Laplacian matrix of the graph G,where D(G) and A(G) are the degree diagonal matrix and the adjacency matrix, respectively.
Bhatnagar S., Merajuddin, Pirzada S.
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Some improved bounds on two energy-like invariants of some derived graphs
Open Mathematics, 2019 Given a simple graph G, its Laplacian-energy-like invariant LEL(G) and incidence energy IE(G) are the sum of square root of its all Laplacian eigenvalues and signless Laplacian eigenvalues, respectively. This paper obtains some improved bounds on LEL and
Cui Shu-Yu, Tian Gui-Xian
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Fractional Revival of Threshold Graphs Under Laplacian Dynamics
Discussiones Mathematicae Graph Theory, 2020 We consider Laplacian fractional revival between two vertices of a graph X. Assume that it occurs at time τ between vertices 1 and 2. We prove that for the spectral decomposition L=∑r=0qθrErL = \sum\nolimits_{r = 0}^q {{\theta _r}{E_r}} of the Laplacian
Kirkland Steve, Zhang Xiaohong
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Bounds on Nirmala energy of graphs
Acta Universitatis Sapientiae: Informatica, 2022 The Nirmala matrix of a graph and its energy have recently defined. In this paper, we establish some features of the Nirmala eigenvalues. Then we propose various bounds on the Nirmala spectral radius and energy. Moreover, we derive a bound on the Nirmala
Yalçin N. Feyza
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Special Matrices, 2017 We take as given a real symmetric matrix A, whose graph is a tree T, and the eigenvalues of A, with their multiplicities. Each edge of T may then be classified in one of four categories, based upon the change in multiplicity of a particular eigenvalue ...
Toyonaga Kenji, Johnson Charles R.
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A survey of the maximal and the minimal nullity in terms of omega invariant on graphs
Acta Universitatis Sapientiae: Mathematica, 2023 Let G = (V, E) be a simple graph with n vertices and m edges. ν(G) and c(G) = m − n + θ be the matching number and cyclomatic number of G, where θ is the number of connected components of G, respectively.
Oz Mert Sinan, Cangul Ismail Naci
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The Maximum Order of Adjacency Matrices With a Given Rank [PDF]
, 2010 AMS Subject Classification: 05B20, 05C50.
Haemers, W.H., Peeters, M.J.P.
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On the Skew Spectra of Cartesian Products of Graphs
Electronic Journal of Combinatorics, 2013 An oriented graph G is a simple undirected graph G with an orientation σ, which assigns to each edge of G a direction so that G becomes a directed graph.
Denglan Cui, Yaoping Hou
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Achievable multiplicity partitions in the inverse eigenvalue problem of a graph
Special Matrices, 2019 Associated to a graph G is a set 𝒮(G) of all real-valued symmetric matrices whose off-diagonal entries are nonzero precisely when the corresponding vertices of the graph are adjacent, and the diagonal entries are free to be chosen.
Adm Mohammad +5 more
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Bounds on normalized Laplacian eigenvalues of graphs
, 2014 Let G be a simple connected graph of order n, where n≥2. Its normalized Laplacian eigenvalues are 0=λ1≤λ2≤⋯≤λn≤2. In this paper, some new upper and lower bounds on λn are obtained, respectively.
Jianxi Li, Ji-Ming Guo, W. Shiu
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