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A051507 Primes p such that p*q+2 is prime, where q is next prime after p. 10
3, 5, 7, 13, 19, 67, 149, 179, 229, 239, 241, 269, 277, 307, 313, 397, 401, 419, 439, 487, 569, 613, 643, 701, 823, 863, 887, 1051, 1289, 1319, 1489, 1609, 1693, 1783, 1873, 1999, 2143, 2239, 2309, 2423, 2539, 2549, 2593, 2617, 2729, 2753, 2819 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

MATHEMATICA

Prime[Select[Range[1000], PrimeQ[Prime[#]*Prime[# + 1] + 2] &]]

Reap[Do[If[PrimeQ[(p=Prime[k])*Prime[k+1]+2], Sow[p]], {k, 1, 430}]][[2, 1]] (* Zak Seidov, Dec 05 2010 *)

PROG

(Sage) A051507 = list(p for p in primes(10**4) if is_prime(p*next_prime(p)+2)) # D. S. McNeil, Dec 04 2010

(PARI) p=2; forprime(q=3, 1e4, if(isprime(p*q+2), print1(p", ")); p=q) \\ Charles R Greathouse IV, May 01 2011

CROSSREFS

Cf. A048880.

Sequence in context: A154700 A187872 A180450 * A173145 A060274 A005235

Adjacent sequences:  A051504 A051505 A051506 * A051508 A051509 A051510

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified April 20 01:55 EDT 2021. Contains 343118 sequences. (Running on oeis4.)