Results 21 to 30 of about 140 (117)
Journal of Inequalities and Applications, 2020 In this paper, we obtain a sharp upper bound on the spectral radius of a nonnegative k-uniform tensor and characterize when this bound is achieved. Furthermore, this result deduces the main result in [X. Duan and B.
Chuang Lv, Lihua You, Xiao-Dong Zhang
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Some upper bounds for the signless Laplacian spectral radius of digraphs [PDF]
Transactions on Combinatorics, 2019 Let $G=(V(G),E(G))$ be a digraph without loops and multiarcs, where $V(G)=\{v_1,v_2,$ $\ldots,v_n\}$ and $E(G)$ are the vertex set and the arc set of $G$, respectively. Let $d_i^{+}$ be the outdegree of the vertex $v_i$.
Weige Xi, Ligong Wang
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On distance signless Laplacian spectrum and energy of graphs
Electronic Journal of Graph Theory and Applications, 2018 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 DQ(G) = Tr(G) + D(G), where D(G) is the distance matrix of G and Tr(G) is the diagonal ...
Abdollah Alhevaz +2 more
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On the Harmonic Index and the Signless Laplacian Spectral Radius of Graphs [PDF]
Kragujevac Journal of Mathematics, 2021 The harmonic index of a conected graph G is defined as H(G) = ∑ uv∈E(G) 2 d(u)+d-(v), where E(G) is the edge set of G, d(u) and d(v) are the degrees of vertices u and v, respectively. The spectral radius of a square matrix M is the maximum among the absolute values of the eigenvalues of M.
HANYUAN DENG +2 more
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The spectral radius of signless Laplacian matrix and sum-connectivity index of graphs
AKCE International Journal of Graphs and Combinatorics, 2022 The sum-connectivity index of a graph G is defined as the sum of weights [Formula: see text] over all edges uv of G, where du and dv are the degrees of the vertices u and v in G, respectively.
A. Jahanbani, S. M. Sheikholeslami
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On the Signless Laplacian Spectral Radius of Cacti
Croatica Chemica Acta, 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 in the class of cacti with perfect matchings and given number of cycles.
Chen, Mingzhu, Zhou, Bo
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Bounds on the α‐Distance Energy and α‐Distance Estrada Index of Graphs
Discrete Dynamics in Nature and Society, Volume 2020, Issue 1, 2020., 2020 Let G be a simple undirected connected graph, then Dα(G) = αTr(G) + (1 − α)D(G) is called the α‐distance matrix of G, where α ∈ [0,1], D(G) is the distance matrix of G, and Tr(G) is the vertex transmission diagonal matrix of G. In this paper, we study some bounds on the α‐distance energy and α‐distance Estrada index of G.
Yang Yang +3 more
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The signless Laplacian spectral radius of graphs with no intersecting triangles [PDF]
Linear Algebra and its Applications, 2021 Let $F_k$ denote the $k$-fan consisting of $k$ triangles which intersect in exactly one common vertex, and $S_{n,k}$ the complete split graph of order $n$ consisting of a clique on $k$ vertices and an independent set on the remaining vertices in which each vertex of the clique is adjacent to each vertex of the independent set.
Yanhua Zhao, Xueyi Huang, Hangtian Guo
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Upper and Lower Bounds for the Spectral Radius of Generalized Reciprocal Distance Matrix of a Graph
Mathematics, 2022 For a connected graph G on n vertices, recall that the reciprocal distance signless Laplacian matrix of G is defined to be RQ(G)=RT(G)+RD(G), where RD(G) is the reciprocal distance matrix, RT(G)=diag(RT1,RT2,⋯,RTn) and RTi is the reciprocal distance ...
Yuzheng Ma, Yubin Gao, Yanling Shao
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The signless Laplacian matrix of hypergraphs
Special Matrices, 2022 In this article, we define signless Laplacian matrix of a hypergraph and obtain structural properties from its eigenvalues. We generalize several known results for graphs, relating the spectrum of this matrix to structural parameters of the hypergraph ...
Cardoso Kauê, Trevisan Vilmar
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