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%I #19 Jun 18 2023 11:41:24
%S 2,66,33330,342999030,2338224387510,9355235774427510,
%T 936123257411127577818510,9601480183016524970884020224910,
%U 394815332706046542049668428841497001870,24675958688943241584150818852261991458372001870
%N Denominator of BernoulliB(10^n).
%H Robert G. Wilson v, <a href="/A139822/b139822.txt">Table of n, a(n) for n = 0..38</a> (a(0)-a(8) from Eric W. Weisstein, a(9)-a(20) from Seiichi Manyama)
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/BernoulliNumber.html">Bernoulli Number</a>
%t Times @@ Select[1 + Divisors[10^n], PrimeQ]
%Y Cf. A114471 (length of a(n)).
%K nonn
%O 0,1
%A _Eric W. Weisstein_, May 01 2008
%E a(9) from _Seiichi Manyama_, Jan 21 2017