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 A062153 #28 Dec 31 2024 14:03:09
%S A062153 0,0,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,3,3,3,3,3,3,3,3,
%T A062153 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,
%U A062153 3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4
%N A062153 a(n) = floor(log_3(n)).
%H A062153 Harry J. Smith, <a href="/A062153/b062153.txt">Table of n, a(n) for n = 1..1000</a>
%F A062153 a(n) = (number of digits of n when written in base 3) - 1.
%F A062153 a(n) = if n > 2 then a(floor(n / 3)) + 1 else 0. - _Reinhard Zumkeller_, Oct 29 2001
%F A062153 G.f.: (1/(1 - x))*Sum_{k>=1} x^(3^k). - _Ilya Gutkovskiy_, Jan 08 2017
%t A062153 Floor[Log[3,Range[120]]] (* _Harvey P. Dale_, Apr 30 2011 *)
%o A062153 (Magma) [ Ilog(3,n) : n in [1..100] ]; // _N. J. A. Sloane_, Dec 23 2006
%o A062153 (PARI) a(n)=logint(n,3) \\ _Charles R Greathouse IV_, Nov 15 2022
%Y A062153 Cf. A000244, A000523, A007089, A102572.
%K A062153 easy,nonn
%O A062153 1,9
%A A062153 _Henry Bottomley_, Jun 06 2001