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 A091635 Number of primes less than 10^n which do not contain the digit 1. 10
 4, 17, 101, 670, 4675, 34425, 262549, 2051466, 16312743, 131464721, 1071368863, 8809580516, 72986908554, 608542410004 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS FORMULA Number of primes less than 10^n after removing any primes with at least one digit 1. a(n) = A006880(n) - A091645(n). EXAMPLE a(2) = 17 because of the 25 primes less than 10^2, 8 have at least one digit 1; 25-8 = 17. 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 *) CROSSREFS Cf. A091634, A091636, A091637, A091638, A091639, A091640, A091641, A091642, A091643. Sequence in context: A024052 A128321 A290352 * A306160 A127676 A232211 Adjacent sequences:  A091632 A091633 A091634 * A091636 A091637 A091638 KEYWORD more,nonn,base AUTHOR Enoch Haga, Jan 30 2004 EXTENSIONS Edited and extended by Robert G. Wilson v, Feb 02 2004 a(9)-a(12) from Donovan Johnson, Feb 14 2008 a(13) from Robert Price, Nov 08 2013 a(14) from Giovanni Resta, Mar 20 2017 STATUS approved

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Last modified September 18 12:00 EDT 2019. Contains 327170 sequences. (Running on oeis4.)