The 2-rotational Steiner triple systems of order 25
β Scribed by Yeow Meng Chee; Gordon F. Royle
- Publisher
- Elsevier Science
- Year
- 1991
- Tongue
- English
- Weight
- 501 KB
- Volume
- 97
- Category
- Article
- ISSN
- 0012-365X
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β¦ Synopsis
In this paper, we enumerate the 2-rotational Steiner triple systems of order 25. There are exactly 140 pairwise non-isomorphic such designs. All these designs have full automorphism groups of order 12. We also investigate the existence of subsystems and quadrilaterals in these designs.
π SIMILAR VOLUMES
We develop some recursive constructions for rotational Steiner triple systems with which the spectrum of a k-rotational Steiner triple system of order v is completely determined for each positive integer k .
## Abstract In this paper, we present a conjecture that is a common generalization of the DoyenβWilson Theorem and Lindner and Rosa's intersection theorem for Steiner triple systems. Given __u__, __v__ β‘ 1,3 (mod 6), __u__ < __v__ < 2__u__β+β 1, we ask for the minimum __r__ such that there exists a
## Phelps 2.1 will produce such a collection for each n -1/> 1. Choose U as in (3.1) above, then B,, =pBn-1 U U is a set of representatives for a CSTS(p"). Since every multiplier m =-1 (modp n'l) is an automorphism of this system f(x)=p"-lx2 +x will be an isomorphism from B,, to another CSTS(p~),
## Abstract In this note, the 80 nonβisomorphic triple systems on 15 points are revisited from the viewpoint of the convex hull of the characteristic vectors of their blocks. The main observation is that the numbers, of facets of these 80 polyhedra are all different, thus producing a new proof of t