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 A230300 #14 Jul 05 2024 14:06:40
%S A230300 1,3,4,6,6,8,9,11,10,12,13,15,15,17,18,20,18,20,21,23,23,25,26,28,27,
%T A230300 29,30,32,32,34,35,37,34,36,37,39,39,41,42,44,43,45,46,48,48,50,51,53,
%U A230300 51,53,54,56,56,58,59,61,60,62,63,65,65,67,68,70,66,68,69,71,71,73,74,76,75,77,78,80,80,82,83,85,83,85
%N A230300 a(n) = n + wt(n-1), where wt() = A000120() is the binary weight.
%C A230300 A228085(m-1) gives the number of times m occurs in this sequence.
%H A230300 <a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a>
%p A230300 a:= n-> n+add(i,i=Bits[Split](n-1)):
%p A230300 seq(a(n), n=1..82); # _Alois P. Heinz_, Jul 05 2024
%t A230300 Table[n+Total[IntegerDigits[n-1,2]],{n,100}] (* _Harvey P. Dale_, May 20 2015 *)
%o A230300 (PARI) a(n) = n + hammingweight(n-1); \\ _Michel Marcus_, Jul 05 2024
%Y A230300 Cf. A000120, A092391, A228085, A230301 (complement).
%K A230300 nonn,base
%O A230300 1,2
%A A230300 _N. J. A. Sloane_, Oct 23 2013