Analytic approximations to the ground-state energy of closed-shell quantum
dots (number of electrons from 2 to 210) are presented in the form of two-point
Pade approximants. These Pade approximants are constructed from the small- and
large-density limits of the energy. We estimated that the maximum error,
reached for intermediate densities, is less than 3%. Within the present
approximation the ground-state is found to be unpolarized.Comment: 4 pages, RevTeX, 3 ps figure