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arXiv · 1912.11627

A Complete Solution to the Cvetković-Rowlinson Conjecture

Huiqiu Lin·Bo Ning
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Abstract

In 1990, Cvetković and Rowlinson [The largest eigenvalue of a graph: a survey, Linear Multilinear Algebra 28(1-2) (1990), 3--33] conjectured that among all outerplanar graphs on $n$ vertices, $K_1\vee P_{n-1}$ attains the maximum spectral radius. In 2017, Tait and Tobin [Three conjectures in extremal spectral graph theory, J. Combin. Theory, Ser. B 126 (2017) 137-161] confirmed the conjecture for sufficiently large values of $n$. In this article, we show the conjecture is true for all $n\geq2$ except for $n=6$.

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Huiqiu Lin, Bo Ning. 2021-01-02. A Complete Solution to the Cvetković-Rowlinson Conjecture. https://doi.org/10.1002/jgt.22667

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