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%I #22 Apr 17 2021 09:08:11
%S 4,17,101,670,4675,34425,262549,2051466,16312743,131464721,1071368863,
%T 8809580516,72986908554,608542410004
%N Number of primes less than 10^n which do not contain the digit 1.
%F Number of primes less than 10^n after removing any primes with at least one digit 1.
%F a(n) = A006880(n) - A091645(n).
%e a(2) = 17 because of the 25 primes less than 10^2, 8 have at least one digit 1; 25-8 = 17.
%t 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], 1] == {}, c++ ]]; Print[c]; p--, {n, 1, 8}] (* _Robert G. Wilson v_, Feb 02 2004 *)
%o (Python)
%o from sympy import sieve # import/use primerange for larger terms
%o def a(n): return sum('1' not in str(p) for p in sieve.primerange(1, 10**n))
%o print([a(n) for n in range(1, 8)]) # _Michael S. Branicky_, Apr 17 2021
%Y Cf. A091634, A091636, A091637, A091638, A091639, A091640, A091641, A091642, A091643.
%K nonn,base,more
%O 1,1
%A _Enoch Haga_, Jan 30 2004
%E Edited and extended by _Robert G. Wilson v_, Feb 02 2004
%E a(9)-a(12) from _Donovan Johnson_, Feb 14 2008
%E a(13) from _Robert Price_, Nov 08 2013
%E a(14) from _Giovanni Resta_, Mar 20 2017
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