Results 71 to 80 of about 2,494 (128)
Linear combinations of graph eigenvalues
, 2006 Let F(G) be a fixed linear combination of the k extremal eigenvalues of a graph G and of its complement. The problem of finding max{F(G):v(G)=n} generalizes a number of problems raised previously in the literature. We show that the limit max{F(G):v(G)=n}/
Nikiforov, Vladimir
core +1 more source
Eccentricity energy change of complete multipartite graphs due to edge deletion
Special Matrices, 2022 The eccentricity matrix ɛ(G) of a graph G is obtained from the distance matrix of G by retaining the largest distances in each row and each column, and leaving zeros in the remaining ones. The eccentricity energy of G is sum of the absolute values of the
Mahato Iswar, Kannan M. Rajesh
doaj +1 more source
Perturbations in a Signed Graph and its Index
Discussiones Mathematicae Graph Theory, 2018 In this paper we consider the behaviour of the largest eigenvalue (also called the index) of signed graphs under small perturbations like adding a vertex, adding an edge or changing the sign of an edge.
Stanić Zoran
doaj +1 more source
Eigenvalues and Perfect Matchings [PDF]
AMS classification: 05C50, 05C70, 05E30.graph;perfect matching;Laplacian matrix;eigenvalues.
Brouwer, A.E., Haemers, W.H.
core +1 more source
On Almost Distance-Regular Graphs [PDF]
2010 Mathematics Subject Classification: 05E30, 05C50;distance-regular graph;walk-regular graph;eigenvalues;predistance ...
Dalfo, C. +4 more
core +1 more source
Cospectral Graphs and the Generalized Adjacency Matrix [PDF]
AMS classifications: 05C50; 05E99;cospectral graphs;generalized spectrum;generalized adjacency ...
Dam, E.R. van +2 more
core +1 more source
Asymptotic Results on the Spectral Radius and the Diameter of Graphs [PDF]
2000 Mathematics Subject Classification: 05C50, 05E99;graphs;spectral radius;diameter;limit points ...
Cioaba, S.M. +3 more
core +1 more source
AMS Subject Classification: 05B05, 05E30, 05C50.Strongly regular graph;Group divisible design;Deza graph;(v;k ...
Haemers, W.H. +2 more
core +1 more source
Signed graphs with strong (anti-)reciprocal eigenvalue property
Special MatricesA (signed) graph is said to exhibit the strong reciprocal (anti-reciprocal) eigenvalue property (SR) (resp., (-SR)) if for any eigenvalue λ\lambda , it has 1λ\frac{1}{\lambda } (resp.,−1λ-\frac{1}{\lambda }) as an eigenvalue as well, with the same ...
Belardo Francesco, Huntington Callum
doaj +1 more source
An Odd Characterization of the Generalized Odd Graphs [PDF]
2010 Mathematics Subject Classification: 05E30, 05C50;distance-regular graphs;generalized odd graphs;odd-girth;spectra of graphs;spectral excess theorem;spectral ...
Dam, E.R. van, Haemers, W.H.
core +1 more source