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 A004727 #18 Apr 22 2021 22:09:37
%S A004727 0,1,2,3,4,5,6,7,9,10,11,12,13,14,15,16,17,1,19,20,21,22,23,24,25,26,
%T A004727 27,2,29,30,31,32,33,34,35,36,37,3,39,40,41,42,43,44,45,46,47,4,49,50,
%U A004727 51,52,53,54,55,56,57,5,59,60,61,62,63,64,65,66,67,6,69,70,71
%N A004727 Delete all 8's from the sequence of nonnegative integers.
%o A004727 (Python)
%o A004727 def A004727(n):
%o A004727 l = len(str(n))
%o A004727 m = 8*(10**l-1)//9
%o A004727 k = n + l - int(n+l < m)
%o A004727 return 7 if k == m else int(str(k).replace('8','')) # _Chai Wah Wu_, Apr 20 2021
%Y A004727 Cf. A004719, A004720, A004721, A004722, A004723, A004724, A004725, A004726, A004728.
%K A004727 base,nonn
%O A004727 0,3
%A A004727 _N. J. A. Sloane_