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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..13.

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: A123750 A024052 A128321 * A127676 A232211 A122940

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

STATUS

approved

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Last modified October 25 14:57 EDT 2014. Contains 248556 sequences.