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arXiv · 1004.0197

Strictly ascending HNN extensions in soluble groups

J. O. Button
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Abstract

We show that there exist finitely generated soluble groups which are not LERF but which do not contain strictly ascending HNN extensions of a cyclic group. This solves Problem 16.2 in the Kourovka notebook. We further show that there is a finitely presented soluble group which is not LERF but which does not contain a strictly ascending HNN extension of a polycyclic group.

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J. O. Button. 2010-04-01. Strictly ascending HNN extensions in soluble groups. https://arxiv.org/abs/1004.0197

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