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A086418 Sum of distinct prime factors of 3-smooth numbers. 2
0, 2, 3, 2, 5, 2, 3, 5, 2, 5, 5, 3, 2, 5, 5, 5, 2, 5, 3, 5, 5, 2, 5, 5, 5, 5, 3, 2, 5, 5, 5, 5, 5, 2, 5, 5, 3, 5, 5, 5, 2, 5, 5, 5, 5, 5, 5, 2, 3, 5, 5, 5, 5, 5, 5, 2, 5, 5, 5, 5, 5, 3, 5, 5, 2, 5, 5, 5, 5, 5, 5, 5, 5, 2, 5, 5, 3, 5, 5, 5, 5, 5, 5, 2, 5, 5, 5, 5, 5, 5, 5, 5, 3, 5, 2, 5, 5, 5, 5, 5, 5, 5 (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(A003586(n));

a(n) = 2*0^(0^A022328(n)) + 3*0^(0^A022329(n)).

MATHEMATICA

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

CROSSREFS

Cf. A003586, A008472, A022328, A022329, A086419, A086417, A086412.

Sequence in context: A260218 A087986 A129088 * A100761 A336964 A027748

Adjacent sequences: A086415 A086416 A086417 * A086419 A086420 A086421

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jul 18 2003

STATUS

approved

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Last modified December 6 10:23 EST 2022. Contains 358630 sequences. (Running on oeis4.)