Packing and Covering Groups with Subgroups
โ Scribed by D. Jungnickel; L. Storme
- Publisher
- Elsevier Science
- Year
- 2001
- Tongue
- English
- Weight
- 182 KB
- Volume
- 239
- Category
- Article
- ISSN
- 0021-8693
No coin nor oath required. For personal study only.
โฆ Synopsis
We study the problem of covering or packing a finite group with subgroups of a specified order and obtain bounds on the size of such covers and packings. Our main results provide characterizations of the elementary abelian groups by the existence of large packings or small covers, respectively. Hence large packings and small covers can be thought of as geometric objects: they correspond to large ลฝ . partial t-spreads and small t-covers of a suitable projective space PG d, p for some prime p. We shall also exhibit some series of examples which show that our bounds are reasonable.
๐ SIMILAR VOLUMES
DEDICATED TO DEREK J. S. ROBINSON ON THE OCCASION OF HIS 60TH BIRTHDAY ## 1. Introduction A group G is called an FC-group if every element x of G has only ลฝ . finitely many conjugates in G, that is, if the centralizer C x has finite G index in G. There exists a wide literature on this subject, and
We study optimal coverings of lattices associated with a given n-cube by frames (= Hamming spheres of radius one) and extended frames under certain constraints, e.g., by constituting at the same time packings of the edge system in such finite lattices. These investigations also yield results on diff
## Abstract A Kirkman holey packing (resp. covering) design, denoted by KHPD(__g^u^__) (resp. KHCD(__g^u^__)), is a resolvable (__gu__, 3, 1) packing (resp. covering) design of pairs with __u__ disjoint holes of size __g__, which has the maximum (resp. minimum) possible number of parallel classes.