A261537 Primes p such that p^7 + 2 is also prime.

53, 449, 521, 653, 881, 983, 1031, 1451, 1571, 1733, 1889, 2129, 2729, 3191, 4259, 5879, 6173, 7499, 7829, 8861, 9743, 9923, 10271, 10313, 11423, 11903, 12041, 12149, 12263, 12329, 12641, 12893, 14591, 14723, 14771, 14813, 15401, 16493, 17783, 18713, 19259

Offset: 1

Author

Vincenzo Librandi, Aug 24 2015

Keywords

• nonn
• easy

Comments

Subsequence of primes of A216980. - Michel Marcus, Aug 24 2015

Examples

			53^7 + 2 = 1174711139839 is a prime.
		

Crossrefs

Cf. A000040, A216980.

Subsequence of A007528.

Cf. similar sequences listed in A261536.

Programs

Magma

[p: p in PrimesUpTo(20000) | IsPrime(p^7+2)];

Maple

A261537:=n->`if`(isprime(n) and isprime(n^7+2), n, NULL): seq(A261537(n), n=1..5*10^4); # Wesley Ivan Hurt, Apr 14 2017

Mathematica

Select[Prime[Range[2500]], PrimeQ[#^7 + 2] &]

PARI

first(m)=my(v=vector(m));i=1;for(j=1,m,while(!isprime((prime(i)^7)+2),i++);v[j]=prime(i);i++);v; \\ Anders Hellström, Aug 24 2015