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arXiv · 0804.2300

Automorphisms of two-dimensional RAAGs and partially symmetric automorphisms of free groups

Kai-Uwe Bux·Ruth Charney·Karen Vogtmann
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Abstract

We compute the virtual cohomological dimension (VCD) of the group of partially symmetric outer automorphisms of a free group. We use this to obtain new upper and lower bounds on the VCD of the outer automorphism group of a two-dimensional right-angled Artin group. In the case of a right-angled group with defining graph a tree, the bounds agree.

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Kai-Uwe Bux, Ruth Charney, Karen Vogtmann. 2008-04-15. Automorphisms of two-dimensional RAAGs and partially symmetric automorphisms of free groups. https://arxiv.org/abs/0804.2300

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