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A108332
Integers k such that 10^k - 89 is prime.
2
2, 3, 637, 2349, 29455, 175093
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".
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, Nov 06 2005 *)
CROSSREFS
KEYWORD
nonn,more
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
a(6) from Riley Fisher, Oct 09 2023
STATUS
approved