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arXiv · 1512.03075

The rational homology of the outer automorphism group of $F_7$

Laurent Bartholdi
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Abstract

We compute the homology groups $H_*(\operatorname{Out}(F_7);\mathbb Q)$ of the outer automorphism group of the free group of rank $7$. We produce in this manner the first rational homology classes of $\operatorname{Out}(F_n)$ that are neither constant ($*=0$) nor Morita classes ($*=2n-4$).

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Laurent Bartholdi. 2015-12-09. The rational homology of the outer automorphism group of $F_7$. https://arxiv.org/abs/1512.03075

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