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A063911
Primes p such that 2*p - 9 is also prime.
2
7, 11, 13, 19, 23, 31, 41, 53, 59, 61, 73, 79, 83, 101, 103, 139, 151, 163, 173, 179, 181, 191, 199, 229, 233, 283, 293, 311, 313, 331, 359, 383, 389, 409, 419, 431, 433, 443, 503, 509, 521, 563, 569, 601, 613, 619, 643, 653, 691, 709, 719
OFFSET
1,1
LINKS
MATHEMATICA
Select[Prime[Range[3, 2000]], PrimeQ[2 # - 9]&] (* Vincenzo Librandi, Feb 02 2014 *)
PROG
(PARI) { n=0; p=1; for (m=1, 10^9, p=nextprime(p+1); if (isprime(2*p - 9), write("b063911.txt", n++, " ", p); if (n==1000, break)) ) } \\ Harry J. Smith, Sep 02 2009
(Magma) [n: n in [4..2000] | IsPrime(n) and IsPrime(2*n-9)]; // Vincenzo Librandi, Feb 02 2014
CROSSREFS
Sequence in context: A091932 A165349 A160024 * A087489 A155488 A100350
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Aug 31 2001
STATUS
approved