A new proof of a theorem of Ivanov and Schupp

2002/08/04 by Delaram Kahrobaei, Kahrobaei, Delaram
Mathematics · #20E05 #FOS: Mathematics #Group Theory (math.GR) #math.GR #msc:20E05

paper · pdf · doi:10.48550/arxiv.math/0208026

arxiv created 2002/08/04 · arxiv updated 2009/11/30

Abstract

The object of this note is to give a very short proof of the following theorem of Ivanov and Schupp. Let H be a finitely generated subgroup of a free group F and the index [F:H] infinite. Then there exists a nontrivial normal subgroup N of F such that N cap H = 1.

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