Finite automata for Schreier graphs of virtually free groups
نویسندگان
چکیده
The Stallings construction for f.g. subgroups of free groups is generalized by introducing the concept of Stallings section, which allows an efficient computation of the core of a Schreier graph based on edge folding. It is proved that those groups admitting Stallings sections are precisely f.g. virtually free groups, through a constructive approach based on Basse-Serre theory. Complexity issues and applications are also discussed.
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تاریخ انتشار 2011