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A Note on Parabolic Subgroups of a Coxeter Group

Dongwen Qi
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Abstract

The aim of this note is to prove that the parabolic closure of any subset of a Coxeter group is a parabolic subgroup. To obtain that, several technical lemmas on the root system of a parabolic subgroup are established.

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Dongwen Qi. 2005-12-17. A Note on Parabolic Subgroups of a Coxeter Group. https://arxiv.org/abs/math/0512408

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