The minimal number of triples required to represent all quintuples on an n-element set is determined for n <= 13 and all extremal constructions are found. In particular we establish that there is a unique minimal system on 13 points, namely the 52 collinear triples of the projective plane of order 3.
Department, Program, or Center
Center for Advancing the Study of CyberInfrastructure
Ars Combinatoria 37 (1994) 13-31
RIT – Main Campus