Book contents
- Frontmatter
- Dedication
- Contents
- Figures
- Tables
- Preface
- Acknowledgements
- 1 Introduction
- 2 Steiner Systems
- 3 The Miracle Octad Generator
- 4 The Binary Golay Code
- 5 Uniqueness of the Steiner System S(5, 8, 24) and the Group M24
- 6 The Hexacode
- 7 Elements of the Mathieu Group M24
- 8 The Maximal Subgroups of M24
- 9 The Mathieu Group M24
- 10 The Leech Lattice M24
- 11 The Conway Group ·O
- 12 Permutation Actions of M24
- 13 Natural Generators of the Mathieu Groups
- 14 Symmetric Generation Using M24
- 15 The Thompson Chain of Subgroups of Co1
- Appendix MAGMA Code for 7★36 : A9 ↦ Co1
- References
- Index
5 - Uniqueness of the Steiner System S(5, 8, 24) and the Group M24
Published online by Cambridge University Press: 31 October 2024
- Frontmatter
- Dedication
- Contents
- Figures
- Tables
- Preface
- Acknowledgements
- 1 Introduction
- 2 Steiner Systems
- 3 The Miracle Octad Generator
- 4 The Binary Golay Code
- 5 Uniqueness of the Steiner System S(5, 8, 24) and the Group M24
- 6 The Hexacode
- 7 Elements of the Mathieu Group M24
- 8 The Maximal Subgroups of M24
- 9 The Mathieu Group M24
- 10 The Leech Lattice M24
- 11 The Conway Group ·O
- 12 Permutation Actions of M24
- 13 Natural Generators of the Mathieu Groups
- 14 Symmetric Generation Using M24
- 15 The Thompson Chain of Subgroups of Co1
- Appendix MAGMA Code for 7★36 : A9 ↦ Co1
- References
- Index
Summary
A sextet is a partition of the 24 points of Ω into six tetrads such that the union of any two of them is an octad. We find all ways in which two sextets can intersect one another and use this knowledge to force any Steiner system S(5, 8, 24) to assume the form of the one given by the MOG. In so doing we show that if a Steiner system S(5, 8, 24) exists then the order of its group of automorphisms is 244, 823, 040 and that it acts quintuply transitively on the 24 points. That the MOG does define an S(5, 8, 24) was proved in Chapter 4.
- Type
- Chapter
- Information
- The Art of Working with the Mathieu Group M24 , pp. 36 - 41Publisher: Cambridge University PressPrint publication year: 2024