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%I #7 Mar 09 2020 09:10:55
%S 2,2,4,2,6,2,4,4,9,4,12,2,8,2,8,4,16,4,8,6,8,4,8,6,12,8,10,4,16,8,16,
%T 4,12,4,6,4,16,4,8,12,8,6,8,4,12,4,8,4,16,8,12,12,16,4,4,8,16,4,4,2,8,
%U 6,8,2,4,4,8,8,8,8,16,4,8,8,4,8,16,6,20,12,6,4,12,16,16,8,24,12,12,8,24
%N Number of divisors of Sum_{i=1..n} prime(i).
%H Amiram Eldar, <a href="/A074369/b074369.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A000005(A007504(n)). - _Amiram Eldar_, Mar 09 2020
%e The number of divisors of prime(1) + prime(2) + prime(3) = 2 + 3 + 5 = 10 is 4, so a(3) = 4.
%t s = 0; l = {}; Do[s = s + Prime[i]; l = Append[l, DivisorSigma[0, s]], {i, 1, 100}]; l
%Y Cf. A000005, A007504.
%K easy,nonn
%O 1,1
%A _Joseph L. Pe_, Sep 24 2002
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