A248480 Consider two consecutive primes {p,q} such that P=2p+q and Q=2q+p are both prime. The sequence gives larger primes q.

5, 7, 17, 61, 107, 127, 227, 251, 271, 347, 499, 787, 797, 827, 919, 929, 1579, 1657, 1733, 1889, 1951, 2099, 2437, 2531, 2767, 2957, 2999, 3001, 3019, 3163, 3371, 3581, 3761, 4241, 4373, 4673, 4919, 5801, 5923, 6229, 6361, 6803, 7057, 7517, 7877, 9337, 9413, 10061, 10399, 11057, 11117, 11171

Offset: 1

Author

Zak Seidov, Oct 07 2014

Keywords

• nonn

Examples

			a(1)=5 because p=3, q=5 and P=11 and Q=13 are both prime.
a(3)=17 because p=13, q=17 and P=43 and Q=47 are both prime.
		

Crossrefs

Cf. A181848 (primes p), A248482 (primes P), A248483 (primes Q).

Programs

Mathematica

Select[Table[If[PrimeQ[2*Prime[j-1] + Prime[j]] && PrimeQ[Prime[j-1] + 2*Prime[j]],Prime[j],0],{j,2,2000}],#!=0&] (* Vaclav Kotesovec, Oct 08 2014 *)

PARI

listq(nn) = {forprime(p=2, nn, q = nextprime(p+1); if (isprime(2*p+q) && isprime(2*q+p), print1(q, ", ")););} \\ Michel Marcus, Oct 07 2014