We construct four flag-transitive symmetric designs having 96 points, blocks of size 20, and 4 blocks on each point-pair. Moreover we prove that these are the only such designs. Our classification completes the classification of flag-transitive, point-imprimitive, symmetric designs with the (constant) number of blocks on a point-pair at most four.
|Journal||Journal of Combinatorial Theory Series A|
|Publication status||Published - 2009|