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arXiv · 1108.2403

A Reidemeister-Schreier theorem for finitely $L$-presented groups

René Hartung
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Abstract

We prove a variant of the well-known Reidemeister-Schreier theorem for finitely $L$-presented groups. More precisely, we prove that each finite index subgroup of a finitely $L$-presented group is itself finitely $L$-presented. Our proof is constructive and it yields a finite $L$-presentation for the subgroup. We further study conditions on a finite index subgroup of an invariantly finitely $L$-presented group to be invariantly $L$-presented itself.

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René Hartung. 2011-08-11. A Reidemeister-Schreier theorem for finitely $L$-presented groups. https://arxiv.org/abs/1108.2403

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