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A333507
Decimal expansion of 1 - ((365!) / ((365 - 23)! * 365^23)).
1
5, 0, 7, 2, 9, 7, 2, 3, 4, 3, 2, 3, 9, 8, 5, 4, 0, 7, 2, 2, 5, 4, 1, 7, 2, 2, 8, 3, 3, 7, 0, 3, 2, 5, 0, 0, 2, 3, 5, 9, 7, 1, 8, 4, 5, 2, 9, 2, 9, 8, 7, 8, 0, 9, 9, 0, 1, 9, 7, 4, 0, 0, 2, 0, 0, 1, 8, 8, 4, 1, 8, 3, 9, 1, 8, 1, 2, 7, 7, 1, 5, 9, 9, 2, 2, 3, 3, 1, 6, 8, 0, 5, 3, 7, 0, 5, 3, 2, 0, 1, 1, 8, 6, 4, 8, 3, 2, 8, 4, 7, 7, 6, 5, 4, 2, 4, 6, 8, 6, 0
OFFSET
0,1
COMMENTS
This is the probability that at least two people in a room of 23 randomly selected people share a birthday, ignoring leap days and assuming days are equiprobable.
This is a rational number; numerator and denominator both have 53 digits. - Charles R Greathouse IV, Jul 11 2020
LINKS
Eric Weisstein's World of Mathematics, Birthday Problem
EXAMPLE
0.5072972343239854072254172283370325...
MATHEMATICA
RealDigits[1- ((365!) / ((365 - 23)! * 365^23)), 10, 120]
PROG
(PARI) 1. - 364!/(342! * 365^22) \\ Charles R Greathouse IV, Mar 25 2020
CROSSREFS
Sequence in context: A070595 A201656 A168195 * A345327 A322712 A244345
KEYWORD
cons,nonn
AUTHOR
Kritsada Moomuang, Mar 25 2020
STATUS
approved