The first example of a simple design
arXiv:2307.08784 · doi:10.1016/j.exco.2021.100005
Abstract
We give the very first example of a simple design. Its points are the elements of the elementary abelian group of order 81 and each block is the union of two parallel lines of the 4-dimensional geometry over the field of order 3. Hence it is also additive.