1,3

a(9) > 2*10^5. - Robert Price, May 17 2014

Table of n, a(n) for n=1..8.

Select[Range[0, 3000], PrimeQ[5^# + #^5 + 1] &]

(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

Cf. A215438.

Sequence in context: A043890 A132355 A241573 * A019416 A138122 A176955

Adjacent sequences: A215439 A215440 A215441 * A215443 A215444 A215445

nonn,more

Vincenzo Librandi, Sep 03 2012

a(7)-a(8) from Robert Price, May 17 2014

approved