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A new proof of a theorem of Ivanov and Schupp

Delaram Kahrobaei
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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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Delaram Kahrobaei. 2002-08-04. A new proof of a theorem of Ivanov and Schupp. https://arxiv.org/abs/math/0208026

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