Overview of NBIBDs by computer search

Cyclic and 1-Rotational designs

These designs have been obtained by computer search. All designs have 1-rotational automorphism groups of order (v-1). They are presented as difference families, one block per line. The invariant treatment is represented as 1000.

For each design is given a heading (Nested Design ...)with the number in the list, the group size, and the invariants of the graph as calculated by the program. The designs are grouped by the parent BIBD (outer block design): some of these give rise to no Nested BIBD but are listed nevertheless.

Designs for v = 8, 12, 16, 18, 20, 21 and 22 are given with k1 from 4 to 10 and k2 from 2 to 5 (where applicable). Note that some of these listings have been severely curtailed, in order to save space.