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A075881
a(n) = the sum of the prime factors of Sum_{i=1..n} prime(i).
1
2, 5, 7, 17, 9, 41, 31, 18, 7, 46, 7, 197, 26, 281, 43, 130, 18, 170, 73, 74, 91, 120, 44, 110, 60, 46, 81, 460, 44, 62, 50, 620, 80, 712, 571, 812, 38, 108, 80, 10, 96, 386, 126, 1280, 74, 1412, 326, 138, 62, 67, 114, 26, 71, 2030, 3171, 71, 239, 230, 3711, 7699
OFFSET
1,1
LINKS
FORMULA
a(n) = A008472(A007504(n)). - Amiram Eldar, Mar 09 2020
EXAMPLE
The sum of the first three primes = 10 = 2 * 5, the prime factors of which sum to 7. Hence a(3) = 7.
MATHEMATICA
Table[Apply[Plus, Transpose[FactorInteger[Sum[Prime[k], {k, 1, i}]]][[1]]], {i, 1, 100}]
CROSSREFS
Sequence in context: A325210 A181447 A082088 * A208241 A089727 A113514
KEYWORD
nonn
AUTHOR
Joseph L. Pe, Oct 16 2002
EXTENSIONS
Offset corrected by Amiram Eldar, Mar 09 2020
STATUS
approved