@Book{1986775801,
author="Gr{\"u}ttm{\"u}ller, Martin
and Roberts, Ian T.
and D'Arcy, Sue
and Egan, Judith",
title="The  minimum number of blocks in Pairwise Balanced Designs with maximum block size 4: the final cases",
series="Preprints aus dem Institut f{\"u}r Mathematik",
year="2005",
address="Germany; Rostock",
abstract="The minimum number of blocks having maximum size precisely four that are required to cover, exactly $\lambda$ times, all pairs of elements from a set of cardinality v is denoted by g$\lambda$(4)(v) are known except for $\lambda$ = 1 andv = 17 or 18. It is known that 30<= g(4)(17) <= 31 and 32 <= g(4)(18) <= 33. In this paper we Show that g(4)(17) =/ 30 and g(4)(18) =/ 32, thus finalising the Determination of g$\lambda$(4)(v) for all $\lambda$ and v<eng>",
note="Martin Gr{\"u}ttm{\"u}ller, Ian T. Roberts, Sue D'Arcy, Judith Egan",
doi="10.18453/rosdok_id00005834",
url="https://purl.uni-rostock.de/rosdok/id00005834",
url="https://doi.org/10.18453/rosdok_id00005834",
language="English"
}