GDDs with two associate classes and with three groups of sizes 1, n and n
نویسندگان
چکیده
A group divisible design GDD(5, n, n; 3, λ1, λ2) is an ordered triple (V,G,B), where V is a 5 + n + n-set of symbols, G is a partition of V into 3 sets of sizes 5, n, n, each set being called group, and B is a collection of 3-subsets (called blocks) of V , such that each pair of symbols from the same group occurs in exactly λ1 blocks; and each pair of symbols from different groups occurs in exactly λ2 blocks. In this paper, we show the necessary conditions are sufficient for the existence of a GDD(5, n, n; 3, λ1, λ2) when λ1 ≥ λ2.
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 58 شماره
صفحات -
تاریخ انتشار 2014