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.
Transitive Steiner triple systems of order 25
β Scribed by Vladimar D Tonchev
- Publisher
- Elsevier Science
- Year
- 1987
- Tongue
- English
- Weight
- 211 KB
- Volume
- 67
- Category
- Article
- ISSN
- 0012-365X
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π SIMILAR VOLUMES
## 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~),
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