Title
On the coexistence of conference matrices and near resolvable 2-(2k+1,k,k-1)2-(2k+1,k,k-1) designs
Abstract
We show that a near resolvable 2-(2k+1,k,k-1) design exists if and only if a conference matrix of order 2k+2 does. A known result on conference matrices then allows us to conclude that a near resolvable 2-(2k+1,k,k-1) design with even k can only exist if 2k+1 is the sum of two squares. In particular, neither a near resolvable 2-(21,10,9) design nor does a near resolvable 2-(33,16,15) design exist. For k⩽14, we also enumerate the near resolvable 2-(2k+1,k,k-1) designs and the corresponding conference matrices.
Year
DOI
Venue
2006
10.1016/j.jcta.2005.05.005
Journal of Combinatorial Theory, Series A
Keywords
DocType
Volume
Conference matrix,near resolvable balanced incomplete block design,NRB,NRBIBD
Journal
113
Issue
ISSN
Citations 
4
0097-3165
0
PageRank 
References 
Authors
0.34
0
3
Name
Order
Citations
PageRank
M GREIG120.82
H HAANPAA200.34
P KASKI300.34