Automatic groups, subgroups and cosets
نویسنده
چکیده
The history, definition and principal properties of automatic groups and their generalisations to subgroups and cosets are reviewed briefly, mainly from a computational perspective. A result about the asynchronous automaticity of an HNN extension is then proved and applied to an example that was proposed by Mark Sapir. AMS Classification 20F32; 20F05
منابع مشابه
On a Class of Double Cosets in Reductive Algebraic Groups
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متن کاملA Model for the Double Cosets of Young Subgroups
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متن کاملA Model for the Double Cosets of Young Subgroups
There are several results concerning double cosets of Young subgroups of symmetric groups which are often proved as corollaries of more general results about Coxeter groups. In this note we give a selection of these results and give them short combinatorial proofs. The replacement for the machinery of Coxeter groups consists of some simple combinatorial arguments involving tableaux. Inevitably ...
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تاریخ انتشار 1998