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%I #30 Mar 06 2024 04:50:15
%S 0,2,9,43,211,1300,8616,62446,469146,3656784,29285501,239911086
%N Number of prime lucky numbers <10^n.
%H <a href="/index/Pri#primepop">Index entries for sequences related to numbers of primes in various ranges</a>
%e a(2) = 9 since there are 9 prime numbers in the lucky number sequence A000959 that are less than 10^2 (3, 7, 13, 31, 37, 43, 67, 73, and 79).
%t lst = Range[1, 10^8, 2]; i = 2; While[ i <= (len = Length@lst) && (k = lst[[i]]) <= len, lst = Drop[lst, {k, len, k}]; i++ ]; Table[Length@ Select[lst, PrimeQ@# && # < 10^n &], {n, 0, 8}] (* _Robert G. Wilson v_, May 12 2006 *)
%Y Cf. A031157, A000959, A000040.
%K nonn,more
%O 0,2
%A _Robert G. Wilson v_, Jun 09 2000
%E a(7)-a(8) from _Robert G. Wilson v_, May 12 2006
%E a(9) from _Donovan Johnson_, Jul 06 2010
%E a(10) from _Kevin P. Thompson_, Nov 22 2021
%E a(11) from _Dana Jacobsen_, Mar 08 2023