A215441 Numbers k such that 3^k + k^3 + 1 is prime.

0, 1, 7, 39, 97, 115, 199, 1287, 1411, 2713, 4647, 84985

Offset: 1

Author

Vincenzo Librandi, Sep 03 2012

Keywords

• nonn

Comments

a(13) > 2*10^5. - Robert Price, Mar 06 2014

Crossrefs

Cf. A215436.

Programs

Magma

[n: n in [0..800] | IsPrime(3^n+n^3+1)];

Mathematica

Select[Range[0, 5000], PrimeQ[3^# + #^3 + 1] & ]

PARI

is(n)=isprime(3^n+n^3+1) \\ Charles R Greathouse IV, Mar 06 2014

Extensions

a(12) from Robert Price, Mar 06 2014