Group divisible designs with block size 4 and group sizes 2 and 5
نویسندگان
چکیده
In this paper we provide a $4$-GDD of type $2^2 5^5$, thereby solving the existence question for last remaining feasible with no more than $30$ points. We then show that $4$-GDDs $2^t 5^s$ exist all but finite specified set pairs $(t,s)$.
منابع مشابه
Splitting group divisible designs with block size 2×4
The necessary conditions for the existence of a (2 × 4, λ)-splitting GDD of type g are gv ≥ 8, λg(v−1) ≡ 0 (mod 4), λg2v(v−1) ≡ 0 (mod 32). It is proved in this paper that these conditions are also sufficient except for λ ≡ 0 (mod 16) and (g, v) = (3, 3).
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ژورنال
عنوان ژورنال: Journal of Combinatorial Designs
سال: 2022
ISSN: ['1520-6610', '1063-8539']
DOI: https://doi.org/10.1002/jcd.21830