Glossary · math
Birthday problem
How many people it takes before two probably share a birthday, or how many spins before a number probably repeats. On a 37-pocket wheel, 8 spins are enough for a better-than-even chance.
In context
It is why results boards are full of repeats: the number of pairs of spins grows much faster than the number of spins, and any pair can match.
Did you know
With 365 birthdays the answer is 23 people. The problem is usually credited to the mathematician Richard von Mises, in 1939.