Hostname: page-component-848d4c4894-x24gv Total loading time: 0 Render date: 2024-05-16T18:27:43.668Z Has data issue: false hasContentIssue false

The Steiner system S(5,8, 24) constructed from dual affine planes

Published online by Cambridge University Press:  14 November 2011

G. A. Kadir
Affiliation:
Department of Mathematics, University of Mostansryah, College of Education, Baghdad, Iraq
J. D. Key
Affiliation:
Department of Mathematics, University of Birmingham, P.O. Box 363, Birmingham B15 2TT, U.K.

Synopsis

We construct firstly a single tactical configuration which has the structure of the dual of the affine plane of order 4, and show how to obtain a further set of 3 such dual planes which, together with , satisfy a certain set of intersection properties. This set of 4 dual planes is used to extend the 20 points of to the Steiner system = S(5, 8, 24). The construction leads to the production of involutions of the type which fix the points of an octad. It is shown that 3 involutions each of this type suffice to generate M24, each of the simple Mathieu groups inside M24, the Todd group, and all the intransitive maximal subgroups of M24.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1986

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1Cannon, J. J.. A Language for Group Theory (Cayley Manual) (Sydney: Sydney University, 1982).Google Scholar
2Curtis, R. T.. A new combinatorial approach to M24. Math. Proc. Cambridge Philos. Soc. 79 (1976), 2542.CrossRefGoogle Scholar
3Curtis, R. T.. The maximal subgroups of M24. Math. Proc. Cambridge Philos. Soc. 81 (1977), 185192.CrossRefGoogle Scholar
4Dembowski, P.. Finite Geometries (Berlin: Springer, 1968).CrossRefGoogle Scholar
5Hughes, D. R. and Piper, F. C.. Projective Planes (Berlin: Springer, 1973).Google Scholar
6Kadir, G. A.. On the Affine Geometries of M24 (Ph.D. Dissertation, Birmingham University, 1984).Google Scholar
7Lüneburg, H.. Transitive Erweiterungen endlicher Permutationsgruppen. Springer Lecture Notes in Mathematics 84 (Berlin: Springer, 1969).Google Scholar
8MacWilliams, F. J. and Sloane, N. J. A.. The Theory of Error Correcting Codes. (North Holland Mathematical Library 16) (Amsterdam: North Holland, 1981).Google Scholar