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arXiv · 2502.13139

Median eigenvalues of subcubic graphs

Hricha Acharya·Benjamin Jeter·Zilin Jiang
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Abstract

We show that the median eigenvalues of every connected graph of maximum degree at most three, except for the Heawood graph, are at most $1$ in absolute value, resolving open problems posed by Fowler and Pisanski, and by Mohar.

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Hricha Acharya, Benjamin Jeter, Zilin Jiang. 2026-08-16. Median eigenvalues of subcubic graphs. https://arxiv.org/abs/2502.13139

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