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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
1, 1093, 795341, 481626601, 262130079485, 132974790903865, 64157156143943045, 29808728817823292065, 13447118719710220490765, 5923562823392985950002825, 2558600264156303883127171925, 1087010123072386037371040127025 (list; graph; refs; listen; history; internal format)
OFFSET

2,2

COMMENTS

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

LINKS

P. Le Conte, Coincident Birthdays.

Mathforum at Drexel, The Birthday Problem. Ask Dr. Math: FAQ.

Eric Weisstein's World of Mathematics, Birthday Problem. Section in World of Mathematics.

FORMULA

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

MATHEMATICA

Q[n_] := (1 - Product[(1 - i/365), {i, 1, n - 1}])365^(n - 1); Table[ Q[n], {n, 2, 13}] (from Robert G. Wilson v Feb 05 2004)

CROSSREFS

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

Sequence in context: A001220 A203858 A115192 * A022197 A124122 A163561

Adjacent sequences:  A091671 A091672 A091673 * A091675 A091676 A091677

KEYWORD

frac,nonn

AUTHOR

Hugo Pfoertner (hugo(AT)pfoertner.org), Feb 03 2004

EXTENSIONS

More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Feb 05 2004

Broken links corrected by S. R. Finch (Steven.Finch(AT)inria.fr), Jan 27 2009

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Last modified February 17 23:54 EST 2012. Contains 206085 sequences.