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 A215443 Numbers k such that 5^k + k^5 - 1 is prime. 1
 1, 3, 9, 13, 27, 225, 505, 1605, 7417, 9193, 9235 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(12) > 2*10^5. - Robert Price, May 24 2014 LINKS MATHEMATICA Select[Range[0, 3000], PrimeQ[5^# + #^5 - 1] &] PROG (MAGMA) [n: n in [0..300] | IsPrime(5^n + n^5 - 1)] (PARI) is(n)=ispseudoprime(5^n+n^5-1) \\ Charles R Greathouse IV, Jun 13 2017 CROSSREFS Cf. A215437. Sequence in context: A018407 A304350 A305913 * A304664 A068885 A305644 Adjacent sequences:  A215440 A215441 A215442 * A215444 A215445 A215446 KEYWORD nonn,more AUTHOR Vincenzo Librandi, Sep 03 2012 EXTENSIONS a(9)-a(11) from Robert Price, May 24 2014 STATUS approved

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Last modified December 9 09:33 EST 2019. Contains 329877 sequences. (Running on oeis4.)