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A108332 Integers n such that 10^n-89 is prime. 2
2, 3, 637, 2349, 29455 (list; graph; refs; listen; history; text; internal format)
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 near-repdigit-related prime numbers.

Index entries for primes involving repunits.

EXAMPLE

n = 3 is a member because: 10^3-89 = 1000-89 = 911, which is prime.

MATHEMATICA

Do[If[PrimeQ[10^n - 89], Print[n]], {n, 2, 10^4}] (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

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

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Last modified September 26 05:09 EDT 2017. Contains 292502 sequences.