On the spectral radius and energy of signless Laplacian matrix of digraphs [PDF]
Heliyon, 2022 Let D be a digraph of order n and with a arcs. The signless Laplacian matrix Q(D) of D is defined as Q(D)=Deg(D)+A(D), where A(D) is the adjacency matrix and Deg(D) is the diagonal matrix of vertex out-degrees of D.
Hilal A. Ganie, Yilun Shang
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Some sufficient conditions on hamilton graphs with toughness [PDF]
Frontiers in Computational Neuroscience, 2022 Let G be a graph, and the number of components of G is denoted by c(G). Let t be a positive real number. A connected graph G is t-tough if tc(G − S) ≤ |S| for every vertex cut S of V(G). The toughness of G is the largest value of t for which G is t-tough,
Gaixiang Cai +4 more
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On the Signless Laplacian Spectral Radius of Bicyclic Graphs with Perfect Matchings [PDF]
The Scientific World Journal, 2014 The graph with the largest signless Laplacian spectral radius among all bicyclic graphs with perfect matchings is determined.
Jing-Ming Zhang +2 more
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Some new sharp bounds for the spectral radius of a nonnegative matrix and its application [PDF]
Journal of Inequalities and Applications, 2017 In this paper, we give some new sharp upper and lower bounds for the spectral radius of a nonnegative irreducible matrix. Using these bounds, we obtain some new and improved bounds for the signless Laplacian spectral radius of a graph or a digraph.
Jun He +3 more
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NEW BOUNDS AND EXTREMAL GRAPHS FOR DISTANCE SIGNLESS LAPLACIAN SPECTRAL RADIUS [PDF]
Journal of Algebraic Systems, 2021 The distance signless Laplacian spectral radius of a connected graph $G$ is the largest eigenvalue of the distance signless Laplacian matrix of $G$, defined as $D^{Q}(G)=Tr(G)+D(G)$, where $D(G)$ is the distance matrix of $G$ and $Tr(G)$ is the diagonal ...
A. Alhevaz, M. Baghipur, S. Paul
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Chromatic number and signless Laplacian spectral radius of graphs [PDF]
Transactions on Combinatorics, 2022 For any simple graph $G$, the signless Laplacian matrix of $G$ is defined as $D(G)+A(G)$, where $D(G)$ and $A(G)$ are the diagonal matrix of vertex degrees and the adjacency matrix of $G$, respectively.
Mohammad Reza Oboudi
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On the Signless Laplacian Spectral Radius of Graphs without Small Books and Intersecting Quadrangles
Mathematics, 2022 In this paper, we determine the maximum signless Laplacian spectral radius of all graphs which do not contain small books as a subgraph and characterize all extremal graphs. In addition, we give an upper bound of the signless Laplacian spectral radius of
Ming-Zhu Chen +3 more
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Some inequalities involving the distance signless Laplacian eigenvalues of graphs [PDF]
Transactions on Combinatorics, 2021 Given a simple graph $G$, the distance signlesss Laplacian $D^{Q}(G)=Tr(G)+D(G)$ is the sum of vertex transmissions matrix $Tr(G)$ and distance matrix $D(G)$.
Abdollah Alhevaz +3 more
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On Distance Signless Laplacian Spectral Radius and Distance Signless Laplacian Energy
Mathematics, 2020 In this article, we find sharp lower bounds for the spectral radius of the distance signless Laplacian matrix of a simple undirected connected graph and we apply these results to obtain sharp upper bounds for the distance signless Laplacian energy graph.
Luis Medina, Hans Nina, Macarena Trigo
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Spectral Sufficient Conditions on Pancyclic Graphs
Complexity, 2021 A pancyclic graph of order n is a graph with cycles of all possible lengths from 3 to n. In fact, it is NP-complete that deciding whether a graph is pancyclic.
Guidong Yu +3 more
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