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Lower bounds for Estrada index and Laplacian Estrada index

โœ Scribed by Hamidreza Bamdad; Firouzeh Ashraf; Ivan Gutman

Publisher
Elsevier Science
Year
2010
Tongue
English
Weight
240 KB
Volume
23
Category
Article
ISSN
0893-9659

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โœฆ Synopsis

Let G be an n-vertex graph. If ฮป 1 , ฮป 2 , . . . , ฮป n and ยต 1 , ยต 2 , . . . , ยต n are the ordinary (adjacency) eigenvalues and the Laplacian eigenvalues of G, respectively, then the Estrada index and the Laplacian Estrada index of G are defined as EE(G) = n i=1 e ฮป i and LEE(G) = n i=1 e ยต i , respectively. Some new lower bounds for EE and LEE are obtained and shown to be the best possible.

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