Free subgroups of the free product of cyclic groups

Stothers, W. W.

doi:10.1090/S0025-5718-1978-0502015-8

Free subgroups of the free product of cyclic groups
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by W. W. Stothers PDF

Math. Comp. 32 (1978), 1274-1280 Request permission

Abstract:

Two kinds of recurrence relation for the number of subgroups of finite index in a free product of finitely many cyclic groups are given. An asymptotic formula is obtained from the first of these relations.

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