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A237812
Primes p such that 2*p+1 and 2*p+13 are also prime.
5
2, 3, 5, 23, 29, 83, 89, 113, 173, 233, 239, 293, 509, 653, 719, 743, 1013, 1049, 1223, 1289, 1499, 2003, 2039, 2063, 2129, 2339, 2393, 2459, 2543, 2693, 2753, 2819, 2963, 3389, 3449, 4409, 4733, 4919, 5039, 6053, 6113, 6263, 6323, 6329, 6449, 7433, 7643
OFFSET
1,1
LINKS
EXAMPLE
23 is in the sequence because 23, 2*23+1 = 47 and 2*23+13 = 59 are all prime.
MATHEMATICA
Select[Prime[Range[10000]], PrimeQ[2 # + 1] && PrimeQ[2 # + 13] &] (* Vincenzo Librandi, Feb 15 2014 *)
Select[Prime[Range[1000]], AllTrue[2#+{1, 13}, PrimeQ]&] (* Harvey P. Dale, Jun 27 2023 *)
PROG
(PARI) s=[]; forprime(p=2, 10000, if(isprime(2*p+1) && isprime(2*p+13), s=concat(s, p))); s
(Magma) [p: p in PrimesUpTo(9200) | IsPrime(2*p+1) and IsPrime(2*p+13)]; // Vincenzo Librandi, Feb 15 2014
CROSSREFS
KEYWORD
nonn
AUTHOR
Colin Barker, Feb 13 2014
STATUS
approved