In probability theory, the birthday paradox states that given a group of 23 (or more) randomly chosen people, the probability is more than 50% that some pair of them will have the same birthday. For 57 or more people, the probability is greater than 99%, although it cannot be exactly 100% unless there are at least 367 people.
The actual birthday problem is asking if any of the 23 people have a matching birthday with any of the others — not one in particular.
si totusi, in ce nisa [if any] raman toate datele astea?