There has been some interest in the alkali metal fullerides, M_nC₆₀(s), because at low temperatures, some of these compounds become superconducting. The alkali metal fullerides are ionic crystals comprising M⁺ ions and C₆₀ⁿ⁻ ions. The value of n can be deduced from the crystal structure. If MnC₆₀ consists of a cubic closest packed array of fulleride ions, with M⁺ ions occupying all the octahedral and tetrahedral holes in the fulleride lattice, then what is the value of n and what is the empirical formula of the fulleride?