Further results about large sets of disjoint Mendelsohn triple systems
โ Scribed by Qingde Kang; Yanxun Chang
- Publisher
- Elsevier Science
- Year
- 1993
- Tongue
- English
- Weight
- 374 KB
- Volume
- 118
- Category
- Article
- ISSN
- 0012-365X
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โฆ Synopsis
In this note, a construction of the large sets of pairwise disjoint Mendelsohn triple systems of order 72k + 6, where k > 1 and k F 1 or 2 (mod 3), is given.
Let X be a set of v elements (v 2 3). A cyclic triple from X is a collection of three pairs (x, y), (y,z) and (z, x), where x,y and z are distinct elements of X. The cyclic triple is denoted by (x, y, z) or ( y, z, x) or (z, x, y). A Mendelsohn triple system on X is a pair (X, B) where B is a collection of cyclic triples from X such that each ordered pair of distinct elements of X is covered by a unique cyclic triple from B. The system on
X( [XI= v) is denoted by MTS(v). Mendelsohn
[l] proved that the spectrum for MTS(u)s is the set of all v-0 or 1 (mod 3) and v#6.
A large set of pairwise disjoint MTS(v)s is a collection of u-2 pairwise disjoint MTS(v)s. It is denoted by LMTS(o). Up to now, all known results about LMTS(v) are: (Rl) There exists an LMTS(u) for v-1,3 (mod 6) [2]; (R2) If there exists an LMTS(v), then there exists an LMTS(3n) [3]; (R3) If there exists an LMTS(V+ 1) and v>,3, then there exists an LMTS(~V+ 1) [3];
(R4) For p-1 or 5 (mod 6), if there exists an LMTS(q +2), then there exists an LMTS(pq + 2) C2,41;
๐ SIMILAR VOLUMES
The spectrum for LMTS(v, 1) has been obtained by Kang and Lei (Bulletin of the ICA, 1993). In this article, firstly, we give the spectrum for LMTS(v,3). Furthermore, by the existence of LMTS(v, 1) and LMTS(v, 3), the spectrum for LMTS(v, A) is completed, that is Y = 2 (mod A), v 2 A + 2, if A # 0 (m
This paper is a continuation of a recent paper by Chen and Stinson, where some recursive constructions for large sets of group-divisible design with block size 3 arc presented. In this paper, we give two new recursive constructions. In particular, we apply these constructions in the case of design