Coupon collector’s problem

For my Probability and Statistics classes I wrote a small application that solves a famous Coupon Collector’s Problem: “A breakfast cereal manufacturer offers a coupon hidden in each package of cereal, and there are K kinds of coupons altogether. The collector wants to have a complete collection of all K coupons. What is the probability P(N,K) that exactly N boxes of cereal will have to be purchased in order to obtain, for the first time, a complete collection of at least one of each of the K kinds of coupons?”

You can download our application here (Windows 64-bit only). The application uses bignum arithmetic and works for any  K and N . The solution was also separately confirmed by numerical simulation. Enjoy!