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arXiv · 1305.0201

On spectral radius of strongly connected digraphs

Jianping Li·Bo Zhou
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Abstract

We determine the digraphs which achieve the second, the third and the fourth minimum spectral radii respectively among strongly connected digraphs of order $n\ge 4$, and thus we answer affirmatively the problem whether the unique digraph which achieves the minimum spectral radius among all strongly connected bicyclic digraphs of order $n$ achieves the second minimum spectral radius among all strongly connected digraphs of order $n$ for $n\ge 4$ proposed in [H. Lin, J. Shu, A note on the spectral characterization of strongly connected bicyclic digraphs, Linear Algebra Appl. 436 (2012) 2524--2530]. We also discuss the strongly connected bicyclic digraphs with small and large spectral radii respectively.

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Jianping Li, Bo Zhou. 2013-05-01. On spectral radius of strongly connected digraphs. https://arxiv.org/abs/1305.0201

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