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A091647
Number of primes less than 10^n having at least one digit 3.
10
1, 9, 66, 561, 4877, 43685, 399564, 3694303, 34433999, 322852288, 3041362298, 28758431735, 272777483044, 2594081699837
OFFSET
1,2
EXAMPLE
a(2) = 9 because of the 25 primes less than 10^2, 9 have at least one digit 3.
MATHEMATICA
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], 3] != {}, c++ ]]; Print[c]; p--, {n, 1, 8}] (* Robert G. Wilson v, Feb 02 2004 *)
KEYWORD
nonn,base
AUTHOR
Enoch Haga, Jan 30 2004
EXTENSIONS
Edited and extended by Robert G. Wilson v, Feb 02 2004
3 more terms from Ryan Propper, Aug 20 2005
a(13) from Robert Price, Nov 11 2013
a(14) from Giovanni Resta, Jul 21 2015
STATUS
approved