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 A004179 #15 May 22 2019 03:35:15
%S A004179 0,1,2,3,0,5,6,7,8,9,10,11,12,13,1,15,16,17,18,19,20,21,22,23,2,25,26,
%T A004179 27,28,29,30,31,32,33,3,35,36,37,38,39,0,1,2,3,0,5,6,7,8,9,50,51,52,
%U A004179 53,5,55,56,57,58,59,60,61,62,63,6,65,66,67,68,69,70,71,72,73,7
%N A004179 Omit 4's from n.
%H A004179 Marius A. Burtea, <a href="/A004179/b004179.txt">Table of n, a(n) for n = 0..10000</a>
%t A004179 Table[FromDigits[DeleteCases[IntegerDigits[n], 4]], {n, 0, 100}] (* _Vincenzo Librandi_, May 22 2019 *)
%o A004179 (PARI) a(n)=subst(Pol(select(k->k-4,digits(n))),'x,10) \\ _Charles R Greathouse IV_, Oct 16 2012
%o A004179 (MATLAB) for u=0:100 ;v=dec2base(u, 10)-'0';v = v(v~=4);
%o A004179 if length(v)>0; sol(u+1)=(str2num(strrep(num2str(v), ' ', '')));else; sol(u+1)=0; end; end;
%o A004179 sol % _Marius A. Burtea_, May 20 2019
%K A004179 nonn,base,easy
%O A004179 0,3
%A A004179 _N. J. A. Sloane_