In this article, we construct directed group divisible designs (DGDDs) with block size five, group-type h n , and index unity. The necessary conditions for the existence of such a DGDD are n โฅ 5, (n -1)h โก 0 (mod 2) and n(n -1)h 2 โก 0 (mod 10). It is shown that these necessary conditions are also su
Existence of HPMDs with block size five
โ Scribed by F. E. Bennett; Y. Chang; J. Yin; H. Zhang
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 194 KB
- Volume
- 5
- Category
- Article
- ISSN
- 1063-8539
No coin nor oath required. For personal study only.
โฆ Synopsis
In this article, it is shown that the necessary condition for the existence of a holey perfect Mendelsohn design (HPMD) with block size 5 and type h n , namely, n โฅ 5 and n(n -1)h 2 โก 0 (mod 5), is also sufficient, except possibly for a few cases. The results of this article guarantee the analogous existence results for group divisible designs (GDDs) of group-type h n with block size k = 5 and having index ฮป = 4. Moreover, some more conclusive results for the existence of (v, 5, 1)-perfect Mendelsohn designs (PMDs) are also mentioned.
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