Academic Editor: Laszlo A. Szekely
Copyright © 2010 Abdullah Al-Azemi and Anton Betten. This is an open access article distributed under the
Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
The 157, 211 triangle-free symmetric configurations are classified and some of their
properties are examined. We conclude that each such configuration has a blocking set. Further
properties like transitivity on lines, self-duality, and self-polarity are discussed.