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 A043534 #15 Jun 22 2024 12:42:06
%S A043534 1,1,1,1,1,1,2,1,2,2,2,2,2,2,2,1,2,2,2,2,2,2,2,1,2,2,2,2,2,2,2,1,2,2,
%T A043534 2,2,2,2,2,1,2,2,2,2,2,2,2,1,2,2,3,3,3,3,3,2,1,2,2,2,2,2,3,2,2,3,3,3,
%U A043534 3,3,2,3,2,3,3,3,3,2,3,3,2,3,3,3,2,3,3,3,2,3
%N A043534 Number of distinct base-7 digits of n.
%H A043534 Robert Israel, <a href="/A043534/b043534.txt">Table of n, a(n) for n = 1..10000</a>
%p A043534 seq(nops(convert(convert(n,base,7),set)), n=1..100); # _Robert Israel_, Sep 18 2016
%t A043534 Table[Length[Union[IntegerDigits[n,7]]],{n,100}] (* _Harvey P. Dale_, Jun 22 2024 *)
%Y A043534 Cf. A007093.
%K A043534 nonn,base
%O A043534 1,7
%A A043534 _Clark Kimberling_