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Coxeter Groups, 2-Completion, Perimeter Reduction and Subgroup Separability

Paul E. Schupp
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Abstract

We show that all groups in a very large class of Coxeter groups are locally quasiconvex and have uniform membership problem solvable in quadratic time. If a group in the class satisfies a further hypothesis it is subgroup separable and relevant homomorphisms are also calculable in quadratic time. The algorithm also decides if a finitely generated subgroup has finite index.

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Paul E. Schupp. 2002-03-02. Coxeter Groups, 2-Completion, Perimeter Reduction and Subgroup Separability. https://arxiv.org/abs/math/0203020

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