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 A091642 #17 Apr 23 2021 11:56:32
%S A091642 4,23,141,915,6375,46799,355805,2774348,22023132,177273427,1443074791,
%T A091642 11855541525,98146301284,817786989282
%N A091642 Number of primes less than 10^n which do not contain the digit 8.
%F A091642 Number of primes less than 10^n after removing any primes with at least one digit 8.
%F A091642 a(n) = A006880(n) - A091709(n).
%e A091642 a(2) = 23 because of the 25 primes less than 10^2, 2 have at least one digit 8; 25-2 = 23.
%t A091642 NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; c = 0; p = 1; Do[ While[ p = NextPrim[p]; p < 10^n, If[ Position[ IntegerDigits[p], 8] == {}, c++ ]]; Print[c]; p--, {n, 1, 8}] (* _Robert G. Wilson v_, Feb 02 2004 *)
%o A091642 (Python)
%o A091642 from sympy import sieve # use slower primerange for larger terms
%o A091642 def a(n): return sum('8' not in str(p) for p in sieve.primerange(2, 10**n))
%o A091642 print([a(n) for n in range(1, 8)]) # _Michael S. Branicky_, Apr 23 2021
%Y A091642 Cf. A091634, A091635, A091636, A091637, A091638, A091639, A091640, A091641, A091643.
%K A091642 more,nonn,base
%O A091642 1,1
%A A091642 _Enoch Haga_, Jan 30 2004
%E A091642 Edited and extended by _Robert G. Wilson v_, Feb 02 2004
%E A091642 a(9)-a(12) from _Donovan Johnson_, Feb 14 2008
%E A091642 a(13) from _Robert Price_, Nov 08 2013
%E A091642 a(14) from _Giovanni Resta_, Mar 20 2017