Local limit theorems are derived for the number of occupied urns in general
finite and infinite urn models under the minimum condition that the variance
tends to infinity. Our results represent an optimal improvement over previous
ones for normal approximation.Comment: Published in at http://dx.doi.org/10.1214/07-AOP350 the Annals of
Probability (http://www.imstat.org/aop/) by the Institute of Mathematical
Statistics (http://www.imstat.org