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A091634 Number of primes less than 10^n which do not contain the digit 0. 30
4, 25, 153, 1010, 7122, 52313, 397866, 3103348, 24649318, 198536215, 1616808581, 13287264748, 110033428309, 917072930187 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..14.

FORMULA

Number of primes less than 10^n after removing any primes with at least one digit 0.

a(n) <= A052386(n) = 9*(9^n-1)/8. - Charles R Greathouse IV, Sep 13 2016

EXAMPLE

a(3) = 153 because there are 168 primes less than 10^3, 15 primes have at least one zero; 168 - 15 = 153.

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], 0] == {}, c++ ]]; Print[c]; p--, {n, 1, 8}] (* Robert G. Wilson v, Feb 02 2004 *)

CROSSREFS

a(n) + A091644(n) = A006880(n).

Cf. A091635, A091636, A091637, A091638, A091639, A091640, A091641, A091642, A091643.

Sequence in context: A072221 A221849 A055846 * A236580 A010909 A079750

Adjacent sequences:  A091631 A091632 A091633 * A091635 A091636 A091637

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 July 25 12:40 EDT 2017. Contains 289795 sequences.