The Estrada Index of Graphs
نویسنده
چکیده
Let G be a simple n-vertex graph whose eigenvalues are λ1, . . . , λn. The Estrada index of G is defined as EE(G) = ∑n i=1 e λi . The importance of this topological index extends much further than just pure graph theory. For example, it has been used to quantify the degree of folding of proteins and to measure centrality of complex networks. The talk aims to give an introduction to the Estrada index and to discuss some techniques used to study it. Selected results on extremal graphs with respect to the Estrada index will also be reviewed.
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