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 A091674 Numerator Q of probability P=Q(n)/365^(n-1) that two or more out of n people share the same birthday. 2

%I

%S 1,1093,795341,481626601,262130079485,132974790903865,

%T 64157156143943045,29808728817823292065,13447118719710220490765,

%U 5923562823392985950002825,2558600264156303883127171925,1087010123072386037371040127025

%N Numerator Q of probability P=Q(n)/365^(n-1) that two or more out of n people share the same birthday.

%C A 365-day year and a uniform distribution of birthdays throughout the year is assumed.

%H P. Le Conte, <a href="http://www.people.fas.harvard.edu/~sfinch/csolve/coincid.pdf">Coincident Birthdays.</a>

%H Mathforum at Drexel, <a href="http://mathforum.org/dr.math/faq/faq.birthdayprob.html">The Birthday Problem.</a> Ask Dr. Math: FAQ.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/BirthdayProblem.html">Birthday Problem.</a> Section in World of Mathematics.

%F Q(n)= (1-product_{i=1..n-1}(1-i/365))*365^(n-1).

%t Q[n_] := (1 - Product[(1 - i/365), {i, 1, n - 1}])365^(n - 1); Table[ Q[n], {n, 2, 13}] (* _Robert G. Wilson v_, Feb 05 2004 *)

%Y Cf. A014088, A091673 Probabilities for exactly two, A091715 Probabilities for three or more.

%K frac,nonn

%O 2,2

%A _Hugo Pfoertner_, Feb 03 2004

%E More terms from _Robert G. Wilson v_, Feb 05 2004

%E Broken links corrected by _Steven Finch_, Jan 27 2009

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Last modified July 25 09:42 EDT 2021. Contains 346289 sequences. (Running on oeis4.)