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A135108
Integers n such that 10^n+39 is a prime number.
1
2, 3, 4, 6, 8, 12, 20, 72, 196, 676, 1528, 1923, 5244, 5379, 6308, 21222, 81778
OFFSET
1,1
LINKS
Makoto Kamada, List of near-repdigit-related prime numbers. (See primecount.txt for terms, primesize.txt for discovery details, including probable or proved primes - search on "10039")
EXAMPLE
6 is a member: 10^6+39 = 1000000+39 = 1000039, which is a prime number.
MATHEMATICA
Select[Range[2000], PrimeQ[10^# + 39] &] (* G. C. Greubel, Sep 23 2016 *)
PROG
(Magma) [n: n in [0..500] |IsPrime(10^n+39)]; // Vincenzo Librandi, Sep 24 2016
KEYWORD
more,nonn
AUTHOR
Julien Peter Benney (jpbenney(AT)gmail.com), Feb 12 2008
EXTENSIONS
a(11)-a(12) from Harvey P. Dale, May 25 2008
a(13)-a(16) from Robert Price, Jan 30 2010
Edited by Ray Chandler, Dec 23 2010
a(17) from Robert Price, Mar 03 2011
STATUS
approved