Results 31 to 40 of about 3,180,841 (100)
The Least Algebraic Connectivity of Graphs
Discrete Dynamics in Nature and Society, Volume 2015, Issue 1, 2015., 2015 The algebraic connectivity of a graph is defined as the second smallest eigenvalue of the Laplacian matrix of the graph, which is a parameter to measure how well a graph is connected. In this paper, we present two unique graphs whose algebraic connectivity attain the minimum among all graphs whose complements are trees, but not stars, and among all ...
Guisheng Jiang +3 more
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The signless Laplacian spread [PDF]
, 2010 The signless Laplacian spread of G is defined as SQ(G)=μ1(G)-μn(G), where μ1(G) and μn(G) are the maximum and minimum eigenvalues of the signless Laplacian matrix of G, respectively. This paper presents some upper and lower bounds for SQ(G).
Liu, Bolian, Liu, Muhuo
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Ain Shams Engineering JournalIn this study, we define the structure formation of the annihilator monic prime graph of commutative rings, whose distinct vertices X and J satisfies a condition annXJ≠annX⋃ann(J), graph is denoted by AMPG(Zn[x]/〈fx〉).
R. Sarathy, J. Ravi Sankar
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The Largest Laplacian Spectral Radius of Unicyclic Graphs with Fixed Diameter
Journal of Applied Mathematics, Volume 2013, Issue 1, 2013., 2013 We identify graphs with the maximal Laplacian spectral radius among all unicyclic graphs with n vertices and diameter d.
Haixia Zhang, Baolin Wang
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, 2018 The \emph{distance matrix} of a simple connected graph $G$ is $D(G)=(d_{ij})$, where $d_{ij}$ is the distance between the $i$th and $j$th vertices of $G$. The \emph{distance signless Laplacian matrix} of the graph $G$ is $D_Q(G)=D(G)+Tr(G)$, where $Tr(G)$
Panigrahi, Pratima, Atik, Fouzul
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Some bounds on spectral radius of signless Laplacian matrix of
, 2023 For a k-graph H = (V(H), E(H)), let B(H) be its incidence matrix, and Q(H) = B(H)B(H)T be its signless Laplacian matrix, and this name comes from the fact that Q(H) is exactly the well-known signless Laplacian matrix for 2-graph.
Zhongxun Zhu, Junhao Zhang
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Spectral Properties of the Harary Signless Laplacian and Harary Incidence Energy
MathematicsLet X be a partitioned matrix and let B its equitable quotient matrix. Consider a simple, undirected, connected graph G of order n. In this paper, we employ a technique based on quotient matrices derived from block-partitioned structures to establish new
Luis Medina +2 more
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On Generalized Harary Eigenvalues and Generalized Join of Graphs
Journal of Mathematics, Volume 2026, Issue 1, 2026.In this work, we further study the generalized Harary matrix of a connected graph G, which we denote by RDα(G). This matrix is defined as the convex combination RDα(G) = αRT(G) + (1 − α)RD(G), where 0 ≤ α ≤ 1. In this formulation, RD(G) refers to the classical Harary matrix, and RT(G) represents a diagonal matrix of reciprocal transmission degrees of G.
Abdollah Alhevaz +4 more
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Refined Lower Bounds for the Laplacian Estrada Index of Connected Graphs via the Two Largest Degrees
Journal of Mathematics, Volume 2026, Issue 1, 2026.Let G be a graph with n vertices and Laplacian eigenvalues μ1, μ2, …, μn. The Laplacian Estrada index of G is defined as LEEG=eμ1+⋯+eμn. In this paper, using the Karush–Kuhn–Tucker optimization framework under inequality constraints, we establish new lower bounds for LEE(G) in terms of the two largest degrees of G.
Hamidreza Bamdad +3 more
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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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