A Reidemeister-schreier Theorem for Finitely L-presented Groups
نویسندگان
چکیده
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. Mathematics Subject Classification (2010): 20F05, 20E07, 20-04
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