. The Kepler conjecture is concerned with the packing constant of 3-balls. Ulam's packing conjecture states that 3-balls have the lowest packing constant of any convex solid. All translations of a fixed body is also a common supply collection of interest, and it defines the translative packing constant of that body. See also Atomic packing factor Sphere packing List of shapes with known packing constant References External links Packing problems Discrete geometry