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 A089792 #11 Apr 21 2022 13:27:12
%S A089792 0,1,2,2,3,4,4,5,6,5,6,7,7,8,9,9,10,11,10,11,12,12,13,14,14,15,16,14,
%T A089792 15,16,16,17,18,18,19,20,19,20,21,21,22,23,23,24,25,24,25,26,26,27,28,
%U A089792 28,29,30,28,29,30,30,31,32,32,33,34,33
%N A089792 a(n) = n-(exponent of highest power of 3 dividing n!).
%C A089792 The exponent of the highest power of 3 dividing binomial(n,k) is given by a(k)+a(n-k)-a(n).
%F A089792 a(n) = a(n-1)+1-A007949(n).
%F A089792 a(n) = log(denominator(n!/3^n))/log(3); a(n) = log_3(A125824(n)). - _Paul Barry_, Apr 02 2007
%F A089792 a(n) = n - A054861(n).
%t A089792 Table[n-IntegerExponent[n!,3],{n,0,70}] (* _Harvey P. Dale_, Aug 09 2015 *)
%o A089792 (PARI) vector(70, n, n--; n-valuation(n!, 3)) \\ _Michel Marcus_, Aug 19 2015
%Y A089792 Cf. A007949, A054861, A125824.
%K A089792 easy,nonn
%O A089792 0,3
%A A089792 _Paul Boddington_, Jan 09 2004