We continue the study of specialized block-colourings of Steiner triple systems initiated in [2] in which the triples through any element are coloured according to a given partition π of the replication number. Such colourings are equitable if π is an equitable partition (i.e., the difference between any two parts of π is at most one). Our main results deal with colourings according to equitable partitions into two, and three parts, respectively.

Authors and Affiliations

1. University of Catania, Catania, Italy

   Mario Gionfriddo & Lorenzo Milazzo

2. University of Washington, Tacoma, WA, USA

   Peter Horák

3. McMaster University, Hamilton, ON, Canada

   Alex Rosa

Reprints and permissions