RBF Definitions
"…when we stack planar groups of triangular aggregates of spheres on top of one another in such a manner that they will be structurally stable without binding agents… we nest six balls in a closest-packed triangular planar array on top of the first triangularly arranged ten-ball aggregate. And on top of these six balls we nest three more. We now have a total of 19 balls. We may now nest one more topmost ball in the one ‘nest’ of the three-ball triangle.
"We now have a symmetrical tetrahedral aggregate consisting of 20 balls without any nuclear ball occurring in the center of the tetrahedral pyramid of balls.
vertical stacking with(2)
"We began our symmetrical base triangle of ten balls and now we have a tetrahedron composed of 20 balls. Just as fingers alone might not have been the only reason for the choice of base ten, fingers and toes together may not have been the only reason the Mayan priests chose congruence in modulo 20, or that 20 was considered a magic number. It might have been the result of an intuitive understanding of closest packing of spheres, which is something more fundamental. For unlike our fingers which lie in a row, the packing of 20 spheres which can be grouped symmetrically together without a nucleus
