Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An increasing sequence of lower bounds for the Estrada index of graphs
  and matrices   Let $G$ be a graph on $n$ vertices and $\lambda_1\geq \lambda_2\geq \ldots
\geq \lambda_n$ its eigenvalues. The Estrada index of $G$ is defined as
$EE(G)=\sum_{i=1}^n e^{\lambda_i}.$ In this work, we using an increasing
sequence converging to the $\lambda_1$ to obtain an increasing sequence of
lower bounds for $EE(G)$. In addition, we generalize this succession for the
Estrada index of an arbitrary nonnegative Hermitian matrix.

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The categories of this paper are: eess
7
The categories of this paper are: hep-th
8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
28
The categories of this paper are: alg-geom
14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
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The categories of this paper are: nlin
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The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio