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A215442
Numbers k such that 5^k + k^5 + 1 is prime.
4
0, 1, 7, 11, 35, 863, 3503, 5101
OFFSET
1,3
COMMENTS
a(9) > 2*10^5. - Robert Price, May 17 2014
MATHEMATICA
Select[Range[0, 3000], PrimeQ[5^# + #^5 + 1] &]
PROG
(Magma) [n: n in [0..200] | IsPrime(5^n + n^5 + 1)]
(PARI) is(n)=ispseudoprime(5^n+n^5+1) \\ Charles R Greathouse IV, May 22 2017
CROSSREFS
Cf. A215438.
Sequence in context: A043890 A132355 A241573 * A019416 A138122 A176955
KEYWORD
nonn,more
AUTHOR
Vincenzo Librandi, Sep 03 2012
EXTENSIONS
a(7)-a(8) from Robert Price, May 17 2014
STATUS
approved