New upper bounds on the spectral radius of graphs

Authors

  • Maryam kargar Department of mathematics, Kerman Branch, Islamic Azad university, Kerman, Iran
  • Tahereh Sistani Department of Mathematics Kerman Branch, Islamic Azad University Kerman, Iran

DOI:

https://doi.org/10.30495/jme.v14i0.1004

Keywords:

eigenvalue, spectral radius, walk, 2-degree

Abstract

We employ the concept of average 2-degree of the vertices and, more generally, the number of walks between two vertices to introduce new upper and lower bounds for the spectral radius and the smallest eigenvalue of a graph. We, further, show how these bounds are better than previous bounds in some cases.

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Published

2019-09-22

Issue

Vol. 14

Section

Vol. 14, No. 4, (2020)

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