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5
                                                                          Crazy Dice
                        at z   1 the denominator has a k-fold zero and so there will be a
                        term    c  k . All the other zeros are roots of unity and, because we
                              (1−zð
                        assumed no common divisiors, all will be of order lower than k.
                                                                                n+k−1
                                                                      c
                           Thus, although the coefficient of the term    k is c       , the
                                                                    (1−zð       k−1

                        coefficients of all other terms  a  j will be aω j n+j    . Since all of
                                                      (1−ωz)             j−1
                        these j are less than k, the sum total of all of these terms is negligible
                                                       n+k−1                     n+k−1
                        compared to our heavy term c        . In short C(n) ∼ c       ,or
                                                       k−1                       k−1
                        even simpler,
                                                           n k−1
                                               C(n) ∼ c           .
                                                         (k − 1)!
                        But, what is c? Although we have deftly avoided the necessity of
                        finding all of the other terms, we cannot avoid this one (it’s the whole
                        story!). So let us write
                                          1                       c
                                                                        + other terms,
                           (1 − z )(1 − z ) ··· (1 − z )      (1 − zð  k
                                                        a k
                                           a 2
                                  a 1
                        multiply by (1 − zð  k  to get
                            1 − z   1 − z       1 − z                 k
                                            ···           c + (1 − zð   × other terms,
                           1 − z a 1  1 − z a 2  1 − z a k

                        and finally let z → 1. By L’Hˆ opital’s rule, for example,  1−z a →  1
                                                                              1−z i    a i
                        whereas each of the other terms times (1 − zð  k  goes to 0. The final
                                        1
                        result is c         , and our final asymptotic formula reads
                                      a 1 a 2 ···a k
                                                          n k−1
                                          C(n) ∼                      .               à 5)
                                                   a 1 a 2 ··· a k (k − 1)!


                        Crazy Dice


                        An ordinary pair of dice consist of two cubes each numbered 1
                        through 6. When tossed together there are altogether 36 (equally
                        likely) outcomes. Thus the sums go from 2 to 12 with varied
                        numbers of repeats for these possibilities. In terms of our ana-
                        lytic representation, each die is associated with the polynomial
                                               5
                              2
                                    3
                                         4
                                                     6
                        z + z + z + z + z + z . The combined possibilities for the
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