A173179 Numbers n such that n^4-n^3-n^2-n-1 is prime.

3, 8, 9, 11, 14, 17, 18, 20, 24, 27, 38, 41, 45, 48, 50, 51, 56, 59, 60, 62, 63, 71, 77, 78, 81, 84, 86, 87, 90, 92, 93, 95, 101, 111, 113, 114, 119, 146, 147, 153, 155, 171, 179, 186, 204, 207, 219, 225, 230, 231, 233, 234, 240, 246, 254, 255, 267, 284, 287, 291

Offset: 1

Author

Vladimir Joseph Stephan Orlovsky, Feb 11 2010

Keywords

• nonn
• easy

Comments

All terms == 0 or 2 (mod 3). - Robert Israel, Mar 09 2020

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A125082, A002328, A162294.

Programs

Magma

[n: n in [2..350] | IsPrime(n^4 - n^3 - n^2 - n - 1)]; // Vincenzo Librandi, Mar 16 2020

Maple

select(t -> isprime(t^4-t^3-t^2-t-1), [$2..1000]); # Robert Israel, Mar 09 2020

Mathematica

f[n_]:=n^4-n^3-n^2-n-1;Select[Range[6! ],PrimeQ[f[ #1]]&]

PARI

is(n)=isprime(n^4-n^3-n^2-n-1) \\ Charles R Greathouse IV, Jun 06 2017

Extensions

Edited by N. J. A. Sloane, Apr 10 2010