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A086294 Sum of distinct prime factors of 7-smooth numbers. 2
0, 2, 3, 2, 5, 5, 7, 2, 3, 7, 5, 9, 8, 2, 5, 7, 10, 5, 5, 3, 9, 10, 2, 12, 5, 7, 12, 8, 5, 7, 7, 5, 9, 10, 10, 2, 14, 5, 8, 7, 3, 12, 10, 5, 9, 7, 15, 5, 9, 10, 5, 12, 2, 8, 14, 5, 10, 10, 7, 5, 12, 12, 10, 10, 5, 9, 7, 17, 5, 9, 8, 10, 3, 12, 7, 12, 2, 10, 14, 5, 12, 10, 15, 7, 5, 12, 7 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A008472(A002473(n)).

MATHEMATICA

sumPrimes[1] = 0; sumPrimes[n_] := Plus @@ First[Transpose[FactorInteger[n]]]; sumPrimes/@Select[Range[500], Max[Transpose[FactorInteger[#]][[1]]] <= 7 &] (* Amiram Eldar, Jan 06 2020 *)

CROSSREFS

Cf. A002473, A008472, A086288, A086293, A086295.

Sequence in context: A137851 A141346 A095402 * A075860 A323171 A008472

Adjacent sequences:  A086291 A086292 A086293 * A086295 A086296 A086297

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jul 15 2003

STATUS

approved

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Last modified September 19 03:31 EDT 2021. Contains 347550 sequences. (Running on oeis4.)