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A215446
Numbers k such that 11^k + k^11 - 1 is prime.
9
1, 7, 27, 43, 87, 223, 11589
OFFSET
1,2
COMMENTS
a(8) > 2*10^5. - Robert Price, Nov 08 2014
MATHEMATICA
Select[Range[0, 5000], PrimeQ[11^# + #^11 - 1] &]
PROG
(Magma) [n: n in [0..2000] | IsPrime(11^n + n^11 - 1)]
(PARI) is(n)=isprime(11^n+n^11-1) \\ Charles R Greathouse IV, Feb 17 2017
CROSSREFS
Sequence in context: A175377 A323113 A205861 * A098948 A015873 A344721
KEYWORD
nonn,hard,more
AUTHOR
Vincenzo Librandi, Sep 06 2012
EXTENSIONS
a(7) from Robert Price, Mar 15 2014
STATUS
approved