Etymology

Today it means: Any of a certain family of graphs related to Keller's conjecture, such that the vertices of the Keller graph of dimension n are the 4ⁿ elements (m₁,...,mₙ) where each m is 0, 1, 2, or 3, and two vertices are joined by an edge if they differ in at least two coordinates and differ by exactly two in at least one coordinate. Full definition →