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 A085423 #16 Feb 18 2024 01:35:11
%S A085423 1,2,3,3,3,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,6,6,6,6,6,6,6,6,6,6,6,6,6,
%T A085423 6,6,6,6,6,6,6,6,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
%U A085423 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,8,8,8,8,8,8,8,8,8,8,8
%N A085423 a(n) = floor(log_2(3n)).
%C A085423 Length of the symmetric signed digit expansion of n with q=2 (i.e., the length of the representation of n in the (-1,0,1)_2 number system).
%C A085423 n occurs A001045(n) times. - _Amiram Eldar_, Feb 18 2024
%H A085423 C. Heuberger and H. Prodinger, <a href="http://dx.doi.org/10.1007/s006070170021">On minimal expansions in redundant number systems: Algorithms and quantitative analysis</a>, Computing 66(2001), 377-393.
%F A085423 a(n) = A000523(A008585(n)). - _Reinhard Zumkeller_, Mar 16 2013
%F A085423 Sum_{n>=1} (-1)^(n+1)/a(n) = log(2) (A002162). - _Amiram Eldar_, Feb 18 2024
%t A085423 Floor[Log[2,3*Range[100]]] (* _Harvey P. Dale_, Oct 15 2016 *)
%o A085423 (Haskell)
%o A085423 a085423 = a000523 . a008585 -- _Reinhard Zumkeller_, Mar 16 2013
%Y A085423 Cf. A005578, A001045.
%Y A085423 Cf. A000523, A008585, A002162.
%K A085423 nonn,easy
%O A085423 1,2
%A A085423 _Ralf Stephan_, Jun 30 2003