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 A182247 #18 Aug 16 2021 17:34:05
%S A182247 0,1,3,7,15,21,31,39,47,57,75,95,111,125,143,159,191,209,243,279,319,
%T A182247 341,383,407,447,473,507,543,575,605,639,671,703,737,803,871,943,1013,
%U A182247 1087,1127,1199,1273,1323,1407,1455,1533
%N A182247 a(0)=0, a(n) = (a(n-1) + n) OR n.
%H A182247 Ivan Panchenko, <a href="/A182247/b182247.txt">Table of n, a(n) for n = 0..1000</a>
%F A182247 a(0)=0, a(n)=(a(n-1)+n) OR n, where OR is the bitwise logical inclusive-OR operator.
%t A182247 nxt[{n_,a_}]:={n+1,BitOr[a+n+1,n+1]}; NestList[nxt,{0,0},50][[All,2]] (* _Harvey P. Dale_, Aug 16 2021 *)
%o A182247 (Python)
%o A182247 a=0
%o A182247 for i in range(1,51):
%o A182247 print(a, end=',')
%o A182247 a += i
%o A182247 a |= i
%K A182247 base,nonn
%O A182247 0,3
%A A182247 _Alex Ratushnyak_, Apr 20 2012