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 A290825 #26 Dec 19 2017 17:57:15
%S A290825 0,1,2,0,1,1,0,1,2,0,0,0,0,1,1,0,1,1,0,0,0,0,1,1,0,1,2,0,0,0,0,0,0,0,
%T A290825 0,0,0,0,0,0,1,1,0,1,1,0,0,0,0,1,1,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,
%U A290825 1,0,1,1,0,0,0,0,1,1,0,1,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
%N A290825 Least base-3 digit of n.
%H A290825 Robert Israel, <a href="/A290825/b290825.txt">Table of n, a(n) for n = 0..10000</a>
%F A290825 a(n) = 2 if and only if n > 0 is in A024023.
%F A290825 a(n) = 0 if n is divisible by 3.
%F A290825 a(n) = min(A010872(n), a(A002264(n))).
%e A290825 11 = 102_3 so a(11)=0.
%p A290825 seq(min(convert(n,base,3)),n=0..100);
%t A290825 Table[Min[IntegerDigits[n,3]],{n,0,120}] (* _Harvey P. Dale_, Dec 19 2017 *)
%o A290825 (PARI) a(n) = if (n==0, 0, vecmin(digits(n, 3))); \\ _Michel Marcus_, Aug 12 2017
%Y A290825 Cf. A002264, A010872, A024023, A037897, A190592.
%K A290825 nonn,base
%O A290825 0,3
%A A290825 _Robert Israel_, Aug 11 2017