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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. 2
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..52.

EXAMPLE

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.

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 *)

PROG

(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

CROSSREFS

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

Sequence in context: A101580 A190663 A123195 * A243844 A271656 A145582

Adjacent sequences:  A248477 A248478 A248479 * A248481 A248482 A248483

KEYWORD

nonn

AUTHOR

Zak Seidov, Oct 07 2014

STATUS

approved

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Last modified February 17 15:32 EST 2020. Contains 331998 sequences. (Running on oeis4.)