A236168 Primes p such that p^3 - p - 1 is prime.

2, 3, 11, 23, 29, 31, 41, 59, 71, 113, 151, 163, 191, 239, 241, 269, 359, 431, 433, 499, 503, 521, 541, 563, 661, 683, 701, 751, 773, 829, 883, 983, 1039, 1259, 1483, 1499, 1511, 1549, 1571, 1609, 1693, 1721, 1759, 1913

Offset: 1

Author

Derek Orr, Jan 19 2014

Keywords

• nonn

Comments

Primes in A126421.

Examples

			269 is prime and 269^3 - 269 - 1 is also prime. So, 269 is a member of this sequence.
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A126421.

Programs

Mathematica

Select[Prime[Range[300]],PrimeQ[#^3-#-1]&] (* Harvey P. Dale, Nov 17 2014 *)

PARI

s=[]; forprime(p=2, 2000, if(isprime(p^3-p-1), s=concat(s, p))); s \\ Colin Barker, Jan 20 2014

Python

import sympy
from sympy import isprime
{print(p) for p in range(10**4) if isprime(p) and isprime(p**3-p-1)}