On the Spectral Characterization of H-Shape Trees

Shengbiao Hu

Department of Mathematics, Qinghai Nationalities University, Xining, China.

DOI: 10.4236/alamt.2014.42005                

Abstract

A graph G is said to be determined by its spectrum if any graph having the same spectrum as G is isomorphic to G. An H-shape is a tree with exactly two of its vertices having maximal degree 3. In this paper, a formula of counting the number of closed 6-walks is given on a graph, and some necessary conditions of a graph Γ cospectral to an H-shape are given.

Keywords

Spectra of Graphs, Cospectral Graphs, Spectra Radius, H-Shape Trees, Determined by Its Spectrum

Conflicts of Interest

The authors declare no conflicts of interest.

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