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%I #15 Mar 09 2020 09:11:02
%S 3,6,18,18,56,42,90,96,217,176,378,198,432,282,630,512,1080,672,1080,
%T 936,1350,912,1440,1404,2268,1760,2480,1832,3420,2400,3960,2472,4032,
%U 2840,3990,3240,5400,2856,4608,5200
%N Sum of the divisors of Sum_{i=1..n} prime(i).
%H Amiram Eldar, <a href="/A074370/b074370.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A000203(A007504(n)). - _R. J. Mathar_, Apr 03 2011
%e sigma(prime(1) + prime(2) + prime(3)) = sigma(10) = 18, so a(3) = 18.
%p A007504 := proc(n) add( ithprime(i),i=1..n) ; end proc:
%p A074370 := proc(n) numtheory[sigma](A007504(n)) ; end proc: # _R. J. Mathar_, Apr 03 2011
%t s = 0; l = {}; Do[s = s + Prime[i]; l = Append[l, DivisorSigma[1, s]], {i, 1, 100}]; l
%t DivisorSigma[1,#]&/@Accumulate[Prime[Range[50]]] (* _Harvey P. Dale_, Mar 13 2011 *)
%Y Cf. A000203, A007504.
%K easy,nonn
%O 1,1
%A _Joseph L. Pe_, Sep 24 2002