Results 61 to 70 of about 68,836 (161)
Merging the A- and Q-spectral theories
, 2016 Let $G$ be a graph with adjacency matrix $A\left( G\right) $, and let $D\left( G\right) $ be the diagonal matrix of the degrees of $G.$ The signless Laplacian $Q\left( G\right) $ of $G$ is defined as $Q\left( G\right) :=A\left( G\right) +D\left( G\right)
Nikiforov, V.
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Distance Spectra of Some Double Join Operations of Graphs
International Journal of Mathematics and Mathematical Sciences, Volume 2024, Issue 1, 2024.In literature, several types of join operations of two graphs based on subdivision graph, Q‐graph, R‐graph, and total graph have been introduced, and their spectral properties have been studied. In this paper, we introduce a new double join operation based on (H1, H2)‐merged subdivision graph.
B. J. Manjunatha +4 more
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Signless Laplacian eigenvalue problems of Nordhaus–Gaddum type [PDF]
Linear Algebra and its Applications, 2019 17 pages, 2 ...
Xueyi Huang, Huiqiu Lin
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The domination number and the least $Q$-eigenvalue [PDF]
, 2013 A vertex set $D$ of a graph $G$ is said to be a dominating set if every vertex of $V(G)\setminus D$ is adjacent to at least a vertex in $D$, and the domination number $\gamma(G)$ ($\gamma$, for short) is the minimum cardinality of all dominating sets of $
Guo, Shu-Guang +3 more
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Signless Laplacians and line graphs
Bulletin: Classe des sciences mathematiques et natturalles, 2005 The spectrum of a graph is the spectrum of its adjacency matrix. The author studies the phenomenon of cospectrality in graphs by comparing characterizing properties of spectra of graphs and spectra of their line graphs. In this comparison spectra of signless Laplacians of graphs are used.
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The signless Laplacian separator of graphs [PDF]
The Electronic Journal of Linear Algebra, 2011 The signless Laplacian separator of a graph is defined as the difference between the largest eigenvalue and the second largest eigenvalue of the associated signless Laplacian matrix. In this paper, we determine the maximum signless Laplacian separators of unicyclic, bicyclic and tricyclic graphs with given order.
Zhifu You, Bolian Liu
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Seidel Laplacian and Seidel Signless Laplacian Energies of Commuting Graph for Dihedral Groups
Malaysian Journal of Fundamental and Applied SciencesIn this paper, we discuss the energy of the commuting graph. The vertex set of the graph is dihedral groups and the edges between two distinct vertices represent the commutativity of the group elements.
M. Romdhini +2 more
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Seidel Signless Laplacian Energy of Graphs
Mathematics Interdisciplinary Research, 2017 Let S(G) be the Seidel matrix of a graph G of order n and let DS(G)=diag(n-1-2d1, n-1-2d2,..., n-1-2dn) be the diagonal matrix with d_i denoting the degree of a vertex v_i in G. The Seidel Laplacian matrix of G is defined as SL(G)=D_S(G)-S(G) and the Seidel signless Laplacian matrix as SL+(G)=DS(G)+S(G).
Ramane, Harishchandra +3 more
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Limit points of (signless) Laplacian spectral radii of linear trees [PDF]
Applied Mathematics and ComputationWe study limit points of the spectral radii of Laplacian matrices of graphs. We adapted the method used by J. B. Shearer in 1989, devised to prove the density of adjacency limit points of caterpillars, to Laplacian limit points.
Francesco Belardo +2 more
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Ordering cacti with signless Laplacian spread
The Electronic Journal of Linear Algebra, 2018 A cactus is a connected graph in which any two cycles have at most one vertex in common. The signless Laplacian spread of a graph is defined as the difference between the largest eigenvalue and the smallest eigenvalue of the associated signless Laplacian matrix. In this paper, all cacti of order n with signless Laplacian spread greater than or equal to
Lin, Zhen, Guo, Shu-Guang
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