A090138 Denominator of the probability that the sum of n uniform picks on [0,1] is first greater than 2 (i.e., the sum of n-1 is not).

1, 1, 6, 3, 40, 90, 336, 56, 51840, 226800, 4435200, 11975040, 188697600, 1210809600, 100590336000, 93405312000, 23712495206400, 2598365952000, 6360528125952, 3754478407680000, 537799391281152000, 802857662698291200

Offset

1,3

Links

Table of n, a(n) for n=1..22.

Eric Weisstein's World of Mathematics, Uniform Sum Distribution.

Formula

a(n) = denominator((n-2)*(2^(n-1)-n)/n!). - Amiram Eldar, Apr 12 2022

Example

0, 0, 1/6, 1/3, 11/40, 13/90, 19/336, ...

Mathematica

a[n_] := Denominator[(n - 2)*(2^(n - 1) - n)/n!]; Array[a, 50] (* Amiram Eldar, Apr 12 2022 *)

Crossrefs

Cf. A090137 (numerators).

Sequence in context: A022666 A202363 A038257 * A229130 A349492 A088390

Adjacent sequences: A090135 A090136 A090137 * A090139 A090140 A090141

Keyword

nonn,frac

Author

Eric W. Weisstein, Nov 22 2003

Status

approved