Introduction to Probability · Problem 3.1.18

Combinatorics — Grinstead & Snell

Mathematics — Probability · permutations

Problem

Consider the problem of finding the probability of more than one coincidence of birthdays in a group of nn people. These include, for example, three people with the same birthday, or two pairs of people with the same birthday, or larger coincidences. Show how you could compute this probability, and write a computer program to carry out this computation. Use your program to find the smallest number of people for which it would be a favorable bet that there would be more than one coincidence of birthdays.

Related theory

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