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%I #5 Sep 10 2019 12:14:03
%S 1,4,6,15,21,74,211,914,4161,21216,115987,678800,4213611,27645078,
%T 190899418,1382961257,10480142165,82864882508,682076806179,
%U 5832742268693,51724158236232,474869816504724,4506715738447347
%N Dirichlet convolution of sigma(n) with Bell numbers.
%t Table[Sum[BellB[n/d - 1]*DivisorSigma[1, d], {d, Divisors[n]}], {n, 1, 30}] (* _Vaclav Kotesovec_, Sep 10 2019 *)
%K nonn
%O 1,2
%A _Erich Friedman_