@Book{1987203445,
author="Greig, M.
and Gr{\"u}ttm{\"u}ller, Martin
and Hartmann, Sven",
title="Pairwise balanced designs whose block size set contains seven and thirteen",
series="Preprints aus dem Institut f{\"u}r Mathematik",
year="2005",
address="Germany; Rostock",
abstract="In this paper, we investigate the PBD-closure of sets K with {\{}7, 13{\}} ⊆ K ⊆ {\{}7, 13, 19, 25, 31, 37, 43{\}}. In particular, we show that v ≡ 1 mod 6, v ≥ 98689 implies v ∈ B({\{}7,13{\}}). As a preliminary result, many new 13-GDDs of type 13^q and resolvable BIBD with block size 6 or 12 are also constructed. Furthermore, we show some elements to be not essential in a Wilson bases for the PBD-closed set {\{}v : v ≡ 1 mod 6, v ≥ 7{\}}.<eng>",
note="M. Greig, M. Gr{\"u}ttm{\"u}ller, S. Hartmann",
doi="10.18453/rosdok_id00005894",
url="https://purl.uni-rostock.de/rosdok/id00005894",
url="https://doi.org/10.18453/rosdok_id00005894",
language="English"
}