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A086295
Sum of all prime factors of 7-smooth numbers.
2
0, 2, 3, 4, 5, 5, 7, 6, 6, 7, 7, 9, 8, 8, 8, 9, 10, 9, 10, 9, 11, 10, 10, 12, 10, 11, 12, 11, 11, 14, 12, 11, 13, 12, 13, 12, 14, 12, 13, 13, 12, 14, 13, 13, 16, 14, 15, 13, 15, 14, 15, 15, 14, 14, 16, 14, 17, 15, 15, 14, 16, 17, 15, 16, 15, 18, 16, 17, 15, 17, 16, 16
OFFSET
1,2
LINKS
FORMULA
a(n) = A001414(A002473(n)).
MATHEMATICA
sumPrimes[1] = 0; sumPrimes[n_] := Plus @@ Times @@@ FactorInteger[n]; sumPrimes/@Select[Range[500], Max[Transpose[FactorInteger[#]][[1]]] <= 7 &] (* Amiram Eldar, Jan 06 2020 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jul 15 2003
STATUS
approved