Martin Grüttmüller
On the PBD-Closure of Sets Containing 3
Preprint series: Preprints aus dem Fachbereich Mathematik, Universität Rostock
05B30 Other designs, configurations, See also {51E30}
Abstract: We describe a method used to prove nonexistence of pairwise
balanced designs. We determine the exact closure of all
subsets $K$ of the set $\{3,4,...,22\}$ with
$K\cap\{11,12,...,22\}\not=\emptyset$ and $3\in K$.
Keywords: pairwise balanced designs, closure, hill-climbing