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arXiv · 2303.05885

The spectral radius of graphs with fractional matching number

Qian-Qian Chen·Ji-Ming Guo
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Abstract

Let $\mathcal{G}_{n, \beta^*}$ $(\mathcal{G}^*_{n,\beta^*})$ be the set of all (connected) graphs of order $n$ with fractional matching number $\beta^*$. In this paper, the graphs with maximal spectral radius in $\mathcal{G}_{n,\beta^*}$ and $\mathcal{G}^*_{n,\beta^*}$ are characterized, respectively. Moreover, a lower bound for the spectral radius in graphs with order $n$ to guarantee the existence of a perfect fractional matching is also given, which generalizes the main result of O [Suil O, Spectral radius and matchings in graphs, Linear Algebra and its Applications, 2020].

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Qian-Qian Chen, Ji-Ming Guo. 2023-03-10. The spectral radius of graphs with fractional matching number. https://arxiv.org/abs/2303.05885

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