Consider n independent trials, each of whichresults in one
Chapter 4, Problem 4.62(choose chapter or problem)
Consider n independent trials, each of whichresults in one of the outcomes 1, . . . , k with respectiveprobabilities p1, . . . , pk,ki=1 pi = 1. Showthat if all the pi are small, then the probability thatno trial outcome occurs more than once is approximatelyequal to exp(n(n 1)i p2i/2)
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