Zobrazeno 1 - 10
of 67
pro vyhledávání: '"Tura, Fernando"'
Autor:
Chen, Guantao, Tura, Fernando C.
Publikováno v:
Special Matrices,2024
In this paper, we give a linear algorithm for obtaining the Laplacian eigenvalues of a cograph. This approach is more efficient as there is no need to directly compute the eigenvalues of Laplacian matrix related to this class of graph. As an applicat
Externí odkaz:
http://arxiv.org/abs/2306.10570
Autor:
Chen Guantao, Tura Fernando C.
Publikováno v:
Special Matrices, Vol 12, Iss 1, Pp 68-81 (2024)
In this article, we give an O(n)O\left(n) time and space algorithm for obtaining the Laplacian eigenvalues of a cograph. This approach is more efficient as there is no need to directly compute the eigenvalues of Laplacian matrix related to this class
Externí odkaz:
https://doaj.org/article/80b98df2fb1b4ba79edb311bafb83545
A graph is said to be I-eigenvalue free if it has no eigenvalues in the interval I with respect to the adjacency matrix A. In this paper we present two algorithms for generating I-eigenvalue free threshold graphs.
Comment: 23 figures, 23 pages
Comment: 23 figures, 23 pages
Externí odkaz:
http://arxiv.org/abs/2110.12107
Autor:
Tura, Fernando
Let $A_n$ be the anti-regular graph of order $n.$ It was conjectured that among all threshold graphs on $n$ vertices, $A_n$ has the smallest positive eigenvalue and the largest eigenvalue less than $-1.$ Recently, in \cite{Cesar2} was given partial r
Externí odkaz:
http://arxiv.org/abs/2006.03136
Autor:
Tura, Fernando
Publikováno v:
MATCH 2012
The eccentricity (anti-adjacency) matrix $\varepsilon(G)$ of a graph $G$ is obtained from the distance matrix by retaining the eccentricities in each row and each column. The $\varepsilon$-eigenvalues of a graph $G$ are those of its eccentricity matr
Externí odkaz:
http://arxiv.org/abs/2002.07140
Autor:
Allem, Luiz Emilio, Tura, Fernando
A graph is called integral if all the eigenvalues of its adjacency matrix are integers. In this paper, we show a cograph that has a balanced cotree $T_{G}(a_{1},\ldots,a_{r-1},0|0,\ldots,0,a_{r})$ is integral computing its spectrum. As an application
Externí odkaz:
http://arxiv.org/abs/1902.06817
A threshold graph G on n vertices is defined by binary sequence of length n. In this paper we present an explicit formula for computing the distance characteristic polynomial of a threshold graph from its binary sequence. As application, we show a se
Externí odkaz:
http://arxiv.org/abs/1811.03061
Autor:
Tura, Fernando
The energy of a graph is defined as the sum the absolute values of the eigenvalues of its adjacency matrix. A threshold graph G on n vertices is coded by a binary sequence of length n. In this paper we answer a question posed by Jacobs et al. [Eigenv
Externí odkaz:
http://arxiv.org/abs/1807.00627
Autor:
Allem, Luiz Emilio, Tura, Fernando
Motivated by the linear time algorithm that locates the eigenvalues of a cograph G [10], we investigate the multiplicity of eigenvalue for \lambda \neq -1,0. For cographs with balanced cotrees we determine explicitly the highest value for the multipl
Externí odkaz:
http://arxiv.org/abs/1801.08972
Autor:
Tura, Fernando
In this paper we present new L-borderenergetic graphs, this is, graphs which are L-noncospectral with Kn but have the same Laplacian energy. We also present some graphs which are noncospectral to respective normalized Laplacian energy and they have t
Externí odkaz:
http://arxiv.org/abs/1611.01461