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The number of subgroups of given index in the modular group*

Published online by Cambridge University Press:  14 February 2012

W. W. Stothers
W. W. Stothers
Affiliation:
Department of Mathematics, University of Glasgow
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Synopsis

A new formula is obtained for the number of subgroups of given index in the modular group. The formula is used to prove a recent conjecture on the parity of the number of subgroups.

Type
Research Article
Information
Proceedings of the Royal Society of Edinburgh Section A: Mathematics , Volume 78 , Issue 1-2 , 1977 , pp. 105 - 112
Copyright
Copyright © Royal Society of Edinburgh 1977

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References

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