Resolvable group divisible designs with block size 3
نویسندگان
چکیده
A group divisible design is resolvable if there exists a partition n = {P,, Pz, . .} of p such that each part Pi is itself a partition of X. In this paper we investigate the existence of resolvable group divisible designs with K = {3}, M a singleton set, and all A. The case where M = { 1) has been solved by Ray-Chaudhuri and Wilson for I = 1, and by Hanani for all h > 1. The case where M is a singleton set, and I = 1 has recently been investigated by Rees and Stinson. We give some small improvements to Rees and Stinson’s results, and give new results for the cases where I > 1. We also investigate a class of designs, introduced by Hanani, which we call frame resolvable group divisible designs and prove necessary and sufficient conditions for their existence.
منابع مشابه
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 77 شماره
صفحات -
تاریخ انتشار 1989