%I #30 Mar 08 2023 05:28:57
%S 1,1,3,6,24,98,240,878,13104,34560,143840,1628640,4421376,27644438,
%T 291751956,1666163520,10523628456,216625138884,779556556800,
%U 5873176163328,107021765366544,633207380826720,6399554302310400,66975753492138600,594616643557427040
%N Sum of the divisors of the n-th Bell number.
%H Amiram Eldar, <a href="/A262349/b262349.txt">Table of n, a(n) for n = 0..104</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/BellNumber.html">Bell Number</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/DivisorFunction.html">Divisor Function</a>
%F a(n) = sigma_1(A000110(n)) = A000203(A000110(n)).
%F a(n) = sigma_1(1/e*Sum_{k >=0} k^n/(k!)).
%t Table[DivisorSigma[1, BellB[n]], {n, 0, 22}]
%o (Magma) [DivisorSigma(1, Bell(n)): n in [0..30]]; // _Vincenzo Librandi_, Sep 19 2015
%o (PARI) a000110(n) = n! * polcoeff( exp( exp( x + x * O(x^n)) - 1), n);
%o vector(30, n, sigma(a000110(n-1))) \\ _Altug Alkan_, Sep 26 2015
%o (PARI) a000110(n) = round(exp(-1)*suminf(k=0, 1.0*k^n/k!));
%o vector(30, n, sigma(a000110(n-1))) \\ _Altug Alkan_, Oct 04 2015
%Y Cf. A000110, A000203.
%K nonn
%O 0,3
%A _Ilya Gutkovskiy_, Sep 18 2015
%E More terms from _Vincenzo Librandi_, Sep 19 2015
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