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%I #7 Jan 29 2020 04:38:57
%S 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,
%T 16,16,16,17,17,17,18,18,18,18,19,19,19,20,20,20,20,21,21,21,22,21,22,
%U 22,22,23,23,23,24,23,24,24,24,25,24,25,25,26,25,26,26,26,27
%N Sum of all prime factors of 3-smooth numbers.
%H Amiram Eldar, <a href="/A086419/b086419.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A001414(A003586(n)).
%F a(n) = 2*A022328(n) + 3*A022329(n).
%t 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 *)
%Y Cf. A001414, A003586, A022328, A022329, A086418, A086417, A069352.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Jul 18 2003
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