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A074370
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Sum of the divisors of Sum_{i=1..n} prime(i).
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1
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3, 6, 18, 18, 56, 42, 90, 96, 217, 176, 378, 198, 432, 282, 630, 512, 1080, 672, 1080, 936, 1350, 912, 1440, 1404, 2268, 1760, 2480, 1832, 3420, 2400, 3960, 2472, 4032, 2840, 3990, 3240, 5400, 2856, 4608, 5200
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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sigma(prime(1) + prime(2) + prime(3)) = sigma(10) = 18, so a(3) = 18.
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MAPLE
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A007504 := proc(n) add( ithprime(i), i=1..n) ; end proc:
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MATHEMATICA
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s = 0; l = {}; Do[s = s + Prime[i]; l = Append[l, DivisorSigma[1, s]], {i, 1, 100}]; l
DivisorSigma[1, #]&/@Accumulate[Prime[Range[50]]] (* Harvey P. Dale, Mar 13 2011 *)
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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