Results 41 to 50 of about 1,304 (147)
Seidel Signless Laplacian Energy of Graphs [PDF]
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.
Harishchandra Ramane +3 more
doaj +1 more source
Sharp Bounds on (Generalized) Distance Energy of Graphs [PDF]
, 2020 Given a simple connected graph G, let D(G) be the distance matrix, DL(G) be the distance Laplacian matrix, DQ(G) be the distance signless Laplacian matrix, and Tr(G) be the vertex transmission diagonal matrix of G.
Alhevaz, Abdollah +3 more
core +1 more source
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
doaj +1 more source
Locating Eigenvalues of a Symmetric Matrix whose Graph is Unicyclic
Trends in Computational and Applied Mathematics, 2021 We present a linear-time algorithm that computes in a given real interval the number of eigenvalues of any symmetric matrix whose underlying graph is unicyclic.
R. O. Braga +2 more
doaj +1 more source
Signless Laplacian determinations of some graphs with independent edges
Karpatsʹkì Matematičnì Publìkacìï, 2018 Let $G$ be a simple undirected graph. Then the signless Laplacian matrix of $G$ is defined as $D_G + A_G$ in which $D_G$ and $A_G$ denote the degree matrix and the adjacency matrix of $G$, respectively.
R. Sharafdini, A.Z. Abdian
doaj +1 more source
A Sharp upper bound for the spectral radius of a nonnegative matrix and applications [PDF]
, 2016 In this paper, we obtain a sharp upper bound for the spectral radius of a nonnegative matrix. This result is used to present upper bounds for the adjacency spectral radius, the Laplacian spectral radius, the signless Laplacian spectral radius, the ...
Shu, Yujie, You, Lihua, Zhang, Xiao-Dong
core +2 more sources
Communications in Advanced Mathematical Sciences, 2018 The signless Laplacian eigenvalues of a graph $G$ are eigenvalues of the matrix $Q(G) = D(G) + A(G)$, where $D(G)$ is the diagonal matrix of the degrees of the vertices in $G$ and $A(G)$ is the adjacency matrix of $G$.
Rao Li
doaj +1 more source
Cospectral constructions for several graph matrices using cousin vertices
Special Matrices, 2021 Graphs can be associated with a matrix according to some rule and we can find the spectrum of a graph with respect to that matrix. Two graphs are cospectral if they have the same spectrum.
Lorenzen Kate
doaj +1 more source
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
doaj +1 more source
A Note on Some Bounds of the α‐Estrada Index of Graphs
Advances in Mathematical Physics, Volume 2020, Issue 1, 2020., 2020 Let G be a simple graph with n vertices. Let A~αG=αDG+1−αAG, where 0 ≤ α ≤ 1 and A(G) and D(G) denote the adjacency matrix and degree matrix of G, respectively. EEαG=∑i=1neλi is called the α‐Estrada index of G, where λ1, ⋯, λn denote the eigenvalues of A~αG. In this paper, the upper and lower bounds for EEα(G) are given.
Yang Yang +3 more
wiley +1 more source