Hostname: page-component-77c89778f8-m42fx Total loading time: 0 Render date: 2024-07-17T01:10:39.118Z Has data issue: false hasContentIssue false

Superimprimitive 2-generator finite groups

Published online by Cambridge University Press:  20 January 2009

A. M. Macbeath
Affiliation:
Department of Mathematics and Statistics, University of Pittsburgh, Pittsburgh, PA 15260, U.S.A.
Rights & Permissions [Opens in a new window]

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

In his thesis, A. A. Hussein Omar, motivated by the study of possible shapes of generic Dirichlet regions for a surface group, made a detailed study for g = 2,3 of the groups generated by pairs (μ, τ) of regular (i.e. fixed-point-free) permutations of order 2,3 respectively and of degree n = 6(2g − 1), such that μ ْ τ is an n-cycle. He observed that, for g = 2,3, precisely one pair generates what he calls a superimprimitive group, and raised the question whether such pairs exist for all g, and, if so, whether they areunique. Our main result is that they do always exist, but that, for large values of g, theyare far from unique. (For details and some motivation for the notation, see [4, 5].)

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 1987

References

REFERENCES

1.Conder, M. D. E., Generators for the alternating and symmetric groups, J. London Math. Soc. 22 (1980), 7586.CrossRefGoogle Scholar
2.Condor, M. D. E., More on generators for the alternating and symmetric groups, Quart. J. Math., Oxford (2) (1981), 137163.CrossRefGoogle Scholar
3.Hall, Marshall, The Theory of Groups (Macmillan, New York, 1961).Google Scholar
4.Hussein Omar, A. A., On some permutation representations of (2,3, n)-groups (Ph.D. Thesis, University of Birmingham, England, 1979).Google Scholar
5.Macbeath, A. M., Generic Dirichlet polygons and the modular group, Glasgow Math. J. 27 (1985), 129141.CrossRefGoogle Scholar
6.Stothers, W. W., Subgroups of infinite index in the modular group, Glasgow Math. J. 19 (1978), 3343.CrossRefGoogle Scholar
7.Stothers, W. W., The number of subgroups of given index in the modular group, Proc. Roy. Soc. Edinburgh 78 A (1977), 105112.CrossRefGoogle Scholar
8.Wilson, R., Introduction to Graph Theory (Longman, London, 1975).Google Scholar
9.Dickson, L. E., Linear Groups, with an exposition of the Galois field theory (Dover reprint, New York, 1958).Google Scholar