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A237813 Primes p such that 2*p+1 and 2*p+15 are also prime. 5
2, 11, 23, 29, 41, 83, 89, 113, 131, 179, 191, 281, 293, 359, 419, 431, 491, 509, 593, 641, 653, 683, 719, 1019, 1049, 1103, 1229, 1289, 1409, 1451, 1511, 1583, 1601, 1811, 1889, 1931, 2003, 2039, 2069, 2129, 2141, 2273, 2393, 2399, 2459, 2543, 2549, 2699 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

EXAMPLE

11 is in the sequence because 11, 2*11+1 = 23 and 2*11+15 = 37 are all prime.

MATHEMATICA

Select[Prime[Range[5000]], PrimeQ[2 # + 1] && PrimeQ[2 # + 15] &] (* Vincenzo Librandi, Feb 15 2014 *)

PROG

(PARI) s=[]; forprime(p=2, 10000, if(isprime(2*p+1) && isprime(2*p+15), s=concat(s, p))); s

(MAGMA) [p: p in PrimesUpTo(4000) | IsPrime(2*p+1) and IsPrime(2*p+15)]; // Vincenzo Librandi, Feb 15 2014

CROSSREFS

Cf. A126107, A237810, A237811, A237812, A237814.

Sequence in context: A066725 A087340 A246622 * A106927 A158189 A218255

Adjacent sequences:  A237810 A237811 A237812 * A237814 A237815 A237816

KEYWORD

nonn

AUTHOR

Colin Barker, Feb 13 2014

STATUS

approved

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Last modified June 15 22:19 EDT 2019. Contains 324145 sequences. (Running on oeis4.)