Some New Lower Bounds for the Estrada Index

Juan L. Aguayo; Juan R. Carmona; Jonnathan Rodríguez

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arXiv · 1910.12139

Some New Lower Bounds for the Estrada Index

Juan L. Aguayo·Juan R. Carmona·Jonnathan Rodríguez

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Abstract

Let $G$ be a graph on $n$ vertices and $\lambda_1,\lambda_2,\ldots,\lambda_n$ its eigenvalues. The Estrada index of $G$ is an invariant that is calculated from the eigenvalues of the adjacency matrix of a graph. In this paper, we present some new lower bounds obtained for the Estrada Index of graphs and in particular of bipartite graphs that only depend on the number of vertices, the number of edges, Randi\'c index, maximum and minimum degree and diameter.

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Juan L. Aguayo, Juan R. Carmona, Jonnathan Rodríguez. 2019-10-26. Some New Lower Bounds for the Estrada Index. https://arxiv.org/abs/1910.12139

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