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arXiv · 1611.05311

On graphs with three or four distinct normalized Laplacian eigenvalues

Xueyi Huang·Qiongxiang Huang
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Abstract

In this paper, we characterize all connected graphs with exactly three distinct normalized Laplacian eigenvalues of which one is equal to $1$, determine all connected bipartite graphs with at least one vertex of degree $1$ having exactly four distinct normalized Laplacian eigenvalues, and find all unicyclic graphs with three or four distinct normalized Laplacian eigenvalues.

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Xueyi Huang, Qiongxiang Huang. 2017-03-27. On graphs with three or four distinct normalized Laplacian eigenvalues. https://arxiv.org/abs/1611.05311

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