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A248483 Consider two consecutive primes {p,q} such that P=2p+q and Q=2q+p are both prime. The sequence gives primes Q. 2

%I

%S 13,19,47,181,317,367,677,743,811,1031,1489,2347,2381,2477,2749,2777,

%T 4729,4951,5189,5657,5851,6287,7297,7583,8287,8867,8969,9001,9049,

%U 9463,10103,10733,11261,12713,13109,14009,14747,17393,17749,18679,19081,20399,21157,22541

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

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

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

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

%o (PARI) listQ(nn) = {forprime(p=2, nn, q = nextprime(p+1); if (isprime(2*p+q) && isprime(Q=2*q+p), print1(Q, ", ")););} \\ _Michel Marcus_, Oct 07 2014

%Y Cf. A181848 (primes p), A248480 (primes q), A248482 (primes P).

%K nonn

%O 1,1

%A _Zak Seidov_, Oct 07 2014

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Last modified April 9 21:21 EDT 2020. Contains 333363 sequences. (Running on oeis4.)