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%I #13 Jul 16 2023 02:10:50
%S 1,2,4,5,6,8,9,10,12,14,15,16,18,21,24,25,26,28,30,32,33,36,40,42,45,
%T 48,52,54,56,60,65,66,68,70,72,74,75,78,80,82,84,87,88,90,92,96,100,
%U 102,105,108,112,114,116,120,125,126,128,132,135,136,140,145,150,151,152
%N a(1)=1. a(n) = the smallest integer > a(n-1) that is divisible by the number of 1's in the binary representation of n.
%H Amiram Eldar, <a href="/A141820/b141820.txt">Table of n, a(n) for n = 1..10000</a>
%e 19 in binary is 10011, which has 3 ones. a(18) = 28. Checking the integers > 28, 29 is not divisible by 3. But 30 is divisible by 3. So a(19) = 30.
%t a[1] = 1; a[n_] := a[n] = Ceiling[(a[n - 1] + 1)/(bw = DigitCount[n, 2, 1])] * bw; Array[a, 100] (* _Amiram Eldar_, Jul 16 2023 *)
%Y Cf. A000120, A141819.
%K nonn,base
%O 1,2
%A _Leroy Quet_, Jul 08 2008
%E Extended by _Ray Chandler_, Jun 21 2009
%E Wrong term 3 removed by _Amiram Eldar_, Jul 16 2023
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