Partitions of sets of designs on seven, eight and nine points
β Scribed by Rudolf Mathon; Anne Penfold Street
- Book ID
- 104340252
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 842 KB
- Volume
- 58
- Category
- Article
- ISSN
- 0378-3758
No coin nor oath required. For personal study only.
β¦ Synopsis
We consider the sets of all possible Steiner triple systems (STS) which can be defined on a 7-set or an 8-set, the sets of all possible Steiner quadruple systems (SQS) which can be defined on an 8-set or a 9-set, and the set of all possible Steiner triple systems, on 9 points each, which can be defined on a 9-set.
By considering the large and overlarge sets of these designs, we derive various strongly regular graphs and balanced or partially balanced designs. We show connections between the overlarge sets of SQS(8), the STS(9) and the resolutions of the set of all (9) triples chosen from a 9-set into 28 parallel classes of three pairwise disjoint triples, with no two parallel classes orthogonal.
Finally we show that the set of all 840 distinct STS(9)'s which can be defined on a given 9-set can be partitioned into 120 large sets of STS(9).
π SIMILAR VOLUMES
The general notion of t-splitting sets is introduced within the context of combinatorial block designs. A greatest lower bound on cardinality of such sets, and an upper bound on cardinality of the smallest such set in a given design are established. The abstraction of t-splitting sets is shown to pr
## Abstract A set of trivial necessary conditions for the existence of a large set of __t__βdesigns, __LS__[N](__t,k,__Ξ½), is $N\big | {{\nu \hskip -3.1 \nu}-i \choose k-i}$ for __i__β=β0,β¦,__t__. There are two conjectures due to Hartman and Khosrovshahi which state that the trivial necessary condi