Spheres of unit diameter are centered at \( (l, m, n) \), where \( l, m, \) and \( n \) take every possible integer value.
The distance between two spheres is computed from the center of one sphere to the center of another sphere.
For a given sphere, \( x \) is the distance to its nearest sphere and \( y \) is the distance to its next nearest sphere.
The value of \( \frac{y}{x} \) is:
