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Subgroups of finite index in a free product with amalgamated subgroup

Author: W. W. Stothers
Journal: Math. Comp. 36 (1981), 653-662
MSC: Primary 20E06; Secondary 10D07, 20E07
MathSciNet review: 606522
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Abstract: Let G be a free product of finitely many finite groups with amalgamated subgroup. Using coset diagrams, a recurrence relation is obtained for the number of subgroups, and of free subgroups, of each finite index in G. In the latter case, an asymptotic formula is derived. When the amalgamated subgroup is central, the relation takes a simpler form.

References [Enhancements On Off] (What's this?)

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Article copyright: © Copyright 1981 American Mathematical Society

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