On the Spectral Characterization of H-Shape Trees

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.

Conflicts of Interest

The authors declare no conflicts of interest.

Cite this paper

Hu, S. (2014) On the Spectral Characterization of H-Shape Trees. Advances in Linear Algebra & Matrix Theory, 4, 79-86. doi: 10.4236/alamt.2014.42005.

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