Maximum two-distance sets in Euclidean spaces of dimension up to twenty-one
A two-distance set is a finite set of points in ℝᵈ whose pairwise distances take exactly two values; g(d) denotes the largest cardinality of such a set. The values g(d) were known for d ≤ 8 (Einhorn–Schoenberg, Lisoněk) and, since a recent computer-assisted classification, for 9 ≤ d ≤ 12, where g(d) = C(d+1, 2) is atta...