Appeared in Algebra Universalis 49(2003), 387-395. [special issue dedicated to the memory of Gian-Carlo Rota]
Written: Oct. 2001
When Dominique Foata and I tried to further generalize the Foata-Han-Lass generalization of the classical Coupon-Collector problem, we were stumped, until Herb Wilf pointed us to a real gem, a short 1960 Monthly Note by Don Newman and Larry Shepp (Shepp's first publication!), that we couldn't find before because they called it the "Dixie Cup" problem. With their brilliant symbolic approach (that Rota would have loved), we finished up this generalization, and the result is this paper, dedicated to the memory of Gian-Carlo Rota.
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