Note on Estrada and $L$-Estrada indices of graphs
Bulletin de l'Académie serbe des sciences. Classe des sciences mathématiques et naturelles, Tome 34 (2009), p. 1
Cet article a éte moissonné depuis la source eLibrary of Mathematical Institute of the Serbian Academy of Sciences and Arts
Let $G$ be a graph of order $n$\,. Let
$\lambda_1,\lambda_2,\ldots,\lambda_n$ be its eigenvalues and
$\mu_1,\mu_2,\ldots,\mu_n$ its Laplacian eigenvalues. The Estrada
index $EE$ of the graph $G$ is defined as the sum of the terms
$e^{\lambda_i} \ , \ i=1,2,\ldots,n$\,. In this paper the notion
of Laplacian--Estrada index ($L$-Estrada index, $LEE$) of a graph
is introduced. It is defined as the sum of the terms $e^{\mu_i} \
, i=1,2,łdots,n$\,. The basic properties of $LEE$ are
established, and compared with the analogous properties of $EE$\,.
In addition, the Estrada and $L$-Estrada indices of some important
classes of graphs are computed.
Classification :
05C50
Keywords: Spectrum (of graph), Laplacian spectrum (of graph), Estrada index, Laplacian-Estrada index
Keywords: Spectrum (of graph), Laplacian spectrum (of graph), Estrada index, Laplacian-Estrada index
@article{BASS_2009_34_a0,
author = {G. H. Fath-Tabar and A. R. Ashrafi and I. Gutman},
title = {Note on {Estrada} and $L${-Estrada} indices of graphs},
journal = {Bulletin de l'Acad\'emie serbe des sciences. Classe des sciences math\'ematiques et naturelles},
pages = {1 },
year = {2009},
volume = {34},
language = {en},
url = {http://geodesic.mathdoc.fr/item/BASS_2009_34_a0/}
}
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%0 Journal Article %A G. H. Fath-Tabar %A A. R. Ashrafi %A I. Gutman %T Note on Estrada and $L$-Estrada indices of graphs %J Bulletin de l'Académie serbe des sciences. Classe des sciences mathématiques et naturelles %D 2009 %P 1 %V 34 %U http://geodesic.mathdoc.fr/item/BASS_2009_34_a0/ %G en %F BASS_2009_34_a0
G. H. Fath-Tabar; A. R. Ashrafi; I. Gutman. Note on Estrada and $L$-Estrada indices of graphs. Bulletin de l'Académie serbe des sciences. Classe des sciences mathématiques et naturelles, Tome 34 (2009), p. 1 . http://geodesic.mathdoc.fr/item/BASS_2009_34_a0/