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%I #10 Apr 12 2022 03:25:55
%S 0,0,1,1,11,13,19,1,247,251,1013,509,1361,1363,16369,2047,65519,851,
%T 233,14563,209711,29959,46091,1048573,5592397,5592401,67108837,
%U 1342177,20648879,268435441,357913931,22369621,4294967263,4294967279
%N Numerator 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).
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/UniformSumDistribution.html">Uniform Sum Distribution</a>.
%F a(n) = numerator((n-2)*(2^(n-1)-n)/n!). - _Amiram Eldar_, Apr 12 2022
%e 0, 0, 1/6, 1/3, 11/40, 13/90, 19/336, ...
%t a[n_] := Numerator[(n - 2)*(2^(n - 1) - n)/n!]; Array[a, 50] (* _Amiram Eldar_, Apr 12 2022 *)
%Y Cf. A090138 (denominators).
%K nonn,frac
%O 1,5
%A _Eric W. Weisstein_, Nov 22 2003