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 A091645 Number of primes less than 10^n having at least one digit 1. 11
 0, 8, 67, 559, 4917, 44073, 402030, 3709989, 34534791, 323587790, 3046685950, 28798331502, 273078628285, 2596399340798 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS EXAMPLE a(2) = 8 because of the 25 primes less than 10^2, 8 have at least one 1 digit. 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], 1] != {}, c++ ]]; Print[c]; p--, {n, 1, 8}] (* Robert G. Wilson v, Feb 02 2004 *) 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], 2] != {}, c++ ]]; Print[c]; p--, {n, 1, 8}] (* Robert G. Wilson v, Feb 02 2004 *) CROSSREFS a(n) + A091635(n) = A006880(n). Cf. A091645, A091646, A091647, A091705, A091706, A091707, A091708, A091709, A091710. Sequence in context: A037594 A037685 A228419 * A015574 A152055 A000434 Adjacent sequences:  A091642 A091643 A091644 * A091646 A091647 A091648 KEYWORD more,nonn,base AUTHOR Enoch Haga, Jan 30 2004 EXTENSIONS Edited, corrected 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

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Last modified October 20 03:03 EDT 2019. Contains 328244 sequences. (Running on oeis4.)