Results 91 to 100 of about 42,138 (164)
New constructions of nonregular cospectral graphs
Special MatricesWe consider two types of joins of graphs G1{G}_{1} and G2{G}_{2}, G1⊻G2{G}_{1}\hspace{0.33em}⊻\hspace{0.33em}{G}_{2} – the neighbors splitting join and G1∨=G2{G}_{1}\mathop{\vee }\limits_{=}{G}_{2} – the nonneighbors splitting join, and compute ...
Hamud Suleiman, Berman Abraham
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Majorization bounds for signless Laplacian eigenvalues
The Electronic Journal of Linear Algebra, 2013 It is known that, for a simple graph G and a real number , the quantity s0 (G) is defined as the sum of the -th power of non-zero singless Laplacian eigenvalues of G. In this paper, first some majorization bounds over s 0(G) are presented in terms of the degree sequences, and number of vertices and edges of G. Additionally, a connection between s 0(G)
Maden, A. Dilek, Cevik, A. Sinan
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On the Signless Laplacian Spectral Radius of Cacti [PDF]
, 2016 A cactus is a connected graph in which any two cycles have at most one vertex in common. We determine the unique graphs with maximum signless Laplacian spectral radius in the class of cacti with given number of cycles (cut edges, respectively) as well as
Chen, Mingzhu +3 more
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Laplacian and signless laplacian spectra and energies of multi-step wheels
Mathematical Biosciences and Engineering, 2020 <abstract> <p>Energies and spectrum of graphs associated to different linear operators play a significant role in molecular chemistry, polymerisation, pharmacy, computer networking and communication systems. In current article, we compute closed forms of signless Laplacian and Laplacian spectra and energies of multi-step wheel networks < ...
Zheng-Qing Chu +4 more
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Universal Adjacency Matrices with Two Eigenvalues [PDF]
AMS Mathematics Subject Classification: 05C50.Adjacency matrix;Universal adjacency matrix;Laplacian matrix;signless Laplacian;Graph spectra;Eigenvalues;Strongly regular ...
Omidi, G.R., Haemers, W.H.
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Computing the reciprocal distance signless Laplacian eigenvalues and energy of graphs [PDF]
, 2019 In this paper, we study the eigenvalues of the reciprocal distance signless Laplacian matrix of a connected graph and obtain some bounds for the maximum eigenvalue of this matrix.
Ramane, Harishchandra +2 more
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Note on a conjecture for the sum of signless Laplacian eigenvalues [PDF]
, 2018 summary:For a simple graph $G$ on $n$ vertices and an integer $k$ with $1\leq k\leq n$, denote by $\mathcal {S}_k^+(G)$ the sum of $k$ largest signless Laplacian eigenvalues of $G$.
Chen, Xiaodan +3 more
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Characterizing the Signless Laplacian H-Spectral Radius for Uniform Directed Hypergraphs
AxiomsThe importance of the signless Laplacian H-spectral radius is highlighted by its known links to connectivity and the maximum cut and independence number.
Hanqing Song +4 more
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Sharp Upper Bounds on the Signless Laplacian Spectral Radius of Strongly Connected Digraphs [PDF]
, 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 +3 more
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Signless laplacian spectral characterization of roses
Kuwait Journal of Science, 2020 A p-rose graph Γ = RG(a3, a4, . . . , as) is a graph consisting of p =a3 + a4 + · · · + as ≥ 2 cycles that all meet in one vertex, and ai (3 ≤ i ≤ s) is the number of cycles in Γ of length i. A graph G is said to be DLS (resp., DQS) if it is determined by the spectrum of its Laplacian (resp. signless Laplacian) matrix, i. e.
Brunetti M, Ashrafi A R, Abdian A Z
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