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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
DOI: https://doi.org/10.1090/S0025-5718-1981-0606522-9
MathSciNet review: 606522
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Abstract | References | Similar Articles | Additional Information

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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Additional Information

DOI: https://doi.org/10.1090/S0025-5718-1981-0606522-9
Article copyright: © Copyright 1981 American Mathematical Society

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