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arXiv · 2610.22774

The Involution Rank of $\MCG(Σ_3)$ Is Four

Abstract

For the closed orientable surface $Σ_3$, we prove \[ \irank\MCG(Σ_3)=4.\] Thus $\MCG(Σ_3)$ can be generated by four involutions, but not by three. This settles the genus-three case of Farb's problem on generation by involutions.

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BibTeXRIS

Qilong Guo, Dongqi Sun. 2026-10-16. The Involution Rank of $\MCG(Σ_3)$ Is Four. https://arxiv.org/abs/2610.22774

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