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 A091709 #21 Apr 24 2021 03:07:05 %S A091709 0,2,27,314,3217,31699,308774,2987107,28824402,277779084,2674980022, %T A091709 25752370493,247919235555,2387154761520 %N A091709 Number of primes less than 10^n having at least one digit 8. %e A091709 a(2) = 2 because of the 25 primes less than 10^2, 2 have at least one digit 8. %t A091709 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 A091709 (Python) %o A091709 from sympy import sieve # use slower primerange for larger terms %o A091709 def a(n): return sum('8' in str(p) for p in sieve.primerange(2, 10**n)) %o A091709 print([a(n) for n in range(1, 8)]) # _Michael S. Branicky_, Apr 23 2021 %Y A091709 a(n) + A091642(n) = A006880(n). %Y A091709 Cf. A091644, A091645, A091646, A091647, A090705, A090706, A091707, A091708, A091710. %K A091709 nonn,base,more %O A091709 1,2 %A A091709 _Enoch Haga_, Jan 30 2004 %E A091709 Edited and extended by _Robert G. Wilson v_, Feb 02 2004 %E A091709 3 more terms from _Ryan Propper_, Aug 22 2005 %E A091709 a(13) from _Robert Price_, Nov 11 2013 %E A091709 a(14) from _Giovanni Resta_, Jul 21 2015