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On the Spectral Characterization of <i>H</i>-Shape Trees
Department of Mathematics, Qinghai Nationalities University, Xining, China
- 1 Department of Mathematics, Qinghai Nationalities University, Xining, China
Advances in Linear Algebra & Matrix Theory·Volume 04 (2014)·Pages 79–86·Published 15 May 2014·DOI10.4236/alamt.2014.42005
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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.
KeywordsSpectra of GraphsCospectral GraphsSpectra Radius<i>H</i>-Shape TreesDetermined by Its Spectrum
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