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A038869
Primes p such that both p-2 and 2p-1 are prime.
3
7, 19, 31, 139, 199, 229, 271, 601, 619, 661, 811, 829, 1279, 1429, 1609, 2029, 2089, 2131, 2311, 2551, 2791, 3169, 3331, 3391, 3529, 3769, 4051, 4159, 4231, 4261, 4339, 4639, 4801, 5419, 5479, 5659, 5851, 6271, 6301, 6361, 6691, 6961, 7561, 7951, 8539
OFFSET
1,1
COMMENTS
Primes p such that A(2*p) - 3*A(p) = 3 (7, 31, 661, 811, 2551, ...) and primes p such that 7*A(p) - A(2*p) = 21 (19, 139, 619, 1429, ...), where A=A288814, are both subsequences of A038869. - David James Sycamore, Aug 07 2017
LINKS
MATHEMATICA
Transpose[Select[Partition[Prime[Range[1200]], 2, 1], #[[2]]-#[[1]]==2 && PrimeQ[2#[[2]]-1]&]][[2]] (* Harvey P. Dale, Jun 19 2014 *)
PROG
(Magma)[n: n in [0..10000]|IsPrime(n) and IsPrime(n-2) and IsPrime(2*n-1)] // Vincenzo Librandi, Dec 18 2010
(PARI) is(n)=n%6==1 && isprime(n-2) && isprime(n) && isprime(2*n-1) \\ Charles R Greathouse IV, Aug 09 2017
CROSSREFS
Cf. A005382.
Sequence in context: A145042 A153892 A338410 * A147503 A147465 A053591
KEYWORD
nonn
AUTHOR
STATUS
approved