The Birthday Problem revisited Every student of probability theory is likely at some point to encounter the birthday problem, which asks how big a group of people needs to be in order for there to be a 50% chance that at least a pair of them share a birthday, on the understanding that each day of the year is equiprobable for a birthday and leaving aside for the purposes of this exercise the equally worthy February 29. If you search the literature, you will find some statements of the birthday...
