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A055728
Number of prime lucky numbers <10^n.
1
0, 2, 9, 43, 211, 1300, 8616, 62446, 469146, 3656784, 29285501, 239911086
OFFSET
0,2
EXAMPLE
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).
MATHEMATICA
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 *)
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Robert G. Wilson v, Jun 09 2000
EXTENSIONS
a(7)-a(8) from Robert G. Wilson v, May 12 2006
a(9) from Donovan Johnson, Jul 06 2010
a(10) from Kevin P. Thompson, Nov 22 2021
a(11) from Dana Jacobsen, Mar 08 2023
STATUS
approved