This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A067371 #10 Jan 29 2020 04:38:29
%S A067371 0,1,1,4,5,12,6,16,32,21,44,27,80,60,112,81,192,156,108,272,216,448,
%T A067371 384,297,640,540,405,1024,912,756,1472,1296,1053,2304,2112,1836,1458,
%U A067371 3328,3024,2592,5120,4800,4320,3645,7424,6912,6156,11264,5103,10752
%N A067371 Arithmetic derivatives of 3-smooth numbers.
%H A067371 Amiram Eldar, <a href="/A067371/b067371.txt">Table of n, a(n) for n = 1..10000</a>
%F A067371 A003415(2^i+3^j) = (3*i + 2*j) * 2^(i-1) * 3^(j-1), i, j >=0.
%F A067371 a(n) = A003415(A003586(n)).
%e A067371 a(18) = A003415(A003586(18)) = A003415(72) = A003415(2^3*3^2) = (3*3+2*2)*2^(3-1)*3^(2-1) = (9+4)*2^2*3^1 = 13*4*3 = 156.
%e A067371 a(27) = A003415(A003586(27)) = A003415(243) = A003415(2^0*3^5) = (3*0+2*5)*2^(0-1)*3^(5-1) = ((0+10)/2)*3^4 = 5*81 = 405.
%t A067371 s = {}; m = 12; Do[n = 3^k; While[n <= 3^m, AppendTo[s, n]; n*=2], {k, 0, m}]; ad[1] = 0; ad[n_] := n * Total @ (Last[#]/First[#] & /@ FactorInteger[n]); ad /@ Union[s] (* _Amiram Eldar_, Jan 29 2020 *)
%Y A067371 Cf. A001787, A003415, A003586, A027471, A022328, A022329.
%K A067371 nonn
%O A067371 1,4
%A A067371 _Reinhard Zumkeller_, Mar 20 2002, revised: Jul 19 2003