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A074370 Sum of the divisors of Sum_{i=1..n} prime(i). 1

%I

%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).

%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 *)

%K easy,nonn

%O 1,1

%A _Joseph L. Pe_, Sep 24 2002

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Last modified January 18 01:05 EST 2020. Contains 330995 sequences. (Running on oeis4.)