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arXiv · 1111.0771

A characterisation of virtually free groups

Robert H. Gilman·S. Hermiller·Derek F. Holt·Sarah Rees
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Abstract

We prove that a finitely generated group $G$ is virtually free if and only if there exists a generating set for $G$ and $k > 0$ such that all $k$-locally geodesic words with respect to that generating set are geodesic.

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Robert H. Gilman, S. Hermiller, Derek F. Holt, Sarah Rees. 2011-11-03. A characterisation of virtually free groups. https://arxiv.org/abs/1111.0771

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