

A108332


Integers k such that 10^k  89 is prime.


2




OFFSET

1,1


COMMENTS

637 corresponds to a certified prime (Primo 2.2.0 beta).  Ryan Propper, Nov 06 2005
No additional terms < 40000.
See Kamada link  primecount.txt for terms, primesize.txt for discovery details including probable or proved primes  search on "9w11".


LINKS

Table of n, a(n) for n=1..5.
Makoto Kamada, List of nearrepdigitrelated prime numbers.
Index entries for primes involving repunits.


EXAMPLE

k = 3 is a term because 10^3  89 = 1000  89 = 911, which is prime.


MATHEMATICA

Do[If[PrimeQ[10^n  89], Print[n]], {n, 2, 10^4}] (* Ryan Propper *)


CROSSREFS

Cf. A089675, A095714, A092767.
Sequence in context: A264577 A165770 A226148 * A256115 A066685 A076155
Adjacent sequences: A108329 A108330 A108331 * A108333 A108334 A108335


KEYWORD

nonn,more,changed


AUTHOR

Julien Peter Benney (jpbenney(AT)ftml.net), Jun 30 2005


EXTENSIONS

a(5) from Robert Price, Dec 15 2010
Edited by Ray Chandler, Dec 23 2010


STATUS

approved



