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arXiv · 0912.3645

On minimal finite quotients of outer automorphism groups of free groups

Mattia Mecchia·Bruno Zimmermann
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Abstract

We prove that, for n=3 and 4, the minimal nonabelian finite factor group of the outer automorphism group Out F_n of a free group of rank n is the linear group PSL_n(Z_2) (conjecturally, this may remain true for arbitrary rank n > 2). We also discuss some computational results on low index subgroups of Aut F_n and Out F_n, for n = 3 and 4, using presentations of these groups.

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Mattia Mecchia, Bruno Zimmermann. 2011-02-02. On minimal finite quotients of outer automorphism groups of free groups. https://arxiv.org/abs/0912.3645

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