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A086419 Sum of all prime factors of 3-smooth numbers. 3
0, 2, 3, 4, 5, 6, 6, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 12, 13, 13, 14, 14, 14, 15, 15, 15, 16, 16, 16, 17, 17, 17, 18, 18, 18, 18, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 22, 21, 22, 22, 22, 23, 23, 23, 24, 23, 24, 24, 24, 25, 24, 25, 25, 26, 25, 26, 26, 26, 27 (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) = A001414(A003586(n)).

a(n) = 2*A022328(n) + 3*A022329(n).

MATHEMATICA

s = {}; m = 12; Do[n = 3^k; While[n <= 3^m, AppendTo[s, n]; n*=2], {k, 0, m}]; sopfr[1] = 0; sopfr[n_] := Plus @@ Times @@@ FactorInteger[n]; sopfr /@ Union[s] (* Amiram Eldar, Jan 29 2020 *)

CROSSREFS

Cf. A001414, A003586, A022328, A022329, A086418, A086417, A069352.

Sequence in context: A195879 A305398 A216522 * A287354 A025548 A121604

Adjacent sequences:  A086416 A086417 A086418 * A086420 A086421 A086422

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jul 18 2003

STATUS

approved

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Last modified September 28 03:16 EDT 2021. Contains 347698 sequences. (Running on oeis4.)