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 A135523 #22 Jul 08 2022 13:23:59
%S A135523 1,2,0,3,0,1,0,4,0,1,0,2,0,1,0,5,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,6,0,1,
%T A135523 0,2,0,1,0,3,0,1,0,2,0,1,0,4,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,7,0,1,0,2,
%U A135523 0,1,0,3,0,1,0,2,0,1,0,4,0,1,0,2,0,1,0,3,0,1,0,2,0,1,0,5,0,1,0,2,0,1,0,3,0
%N A135523 a(n) = A007814(n) + A209229(n).
%H A135523 Antti Karttunen, <a href="/A135523/b135523.txt">Table of n, a(n) for n = 1..65537</a>
%F A135523 G.f.: x + Sum_{k>=1} x^(2^k)*(1 + 1/(1 - x^(2^k))). - _Ilya Gutkovskiy_, Mar 30 2017
%F A135523 a(n) = A135560(n) - 1. _Antti Karttunen_, Sep 27 2018
%p A135523 GS(4,1,200); [see A135416].
%o A135523 (PARI) A135523(n) = (valuation(n,2)+(n && !bitand(n,n-1))); \\ _Antti Karttunen_, Sep 27 2018
%o A135523 (Python)
%o A135523 def A135523(n): return (~n& n-1).bit_length()+int(not(n&-n)^n) # _Chai Wah Wu_, Jul 08 2022
%Y A135523 Cf. A135416, A007814, A036987.
%Y A135523 This is Guy Steele's sequence GS(4, 1) (see A135416).
%Y A135523 One less than A135560.
%K A135523 nonn,easy
%O A135523 1,2
%A A135523 _N. J. A. Sloane_, based on a message from Guy Steele and _Don Knuth_, Mar 01 2008