where {<10} is the permutation of the ten digits (0 1 2 3 4 5 6 7 8 9) and {≤5} is the permutation of the six digits (0 1 2 3 4 5). The 𝜉"i" and 𝜉"j" coordinates range over the 10 vertices of great circle decagons; even and odd digits label the vertices of the two great circle pentagons inscribed in each decagon. The 𝜂 coordinate ranges over the 6 non-orthogonal great circle decagons that intersect at each vertex.