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A051507 Primes p such that p*q+2 is prime, where q is next prime after p. 10

%I

%S 3,5,7,13,19,67,149,179,229,239,241,269,277,307,313,397,401,419,439,

%T 487,569,613,643,701,823,863,887,1051,1289,1319,1489,1609,1693,1783,

%U 1873,1999,2143,2239,2309,2423,2539,2549,2593,2617,2729,2753,2819

%N Primes p such that p*q+2 is prime, where q is next prime after p.

%H Charles R Greathouse IV, <a href="/A051507/b051507.txt">Table of n, a(n) for n = 1..10000</a>

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

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

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

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

%Y Cf. A048880.

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_

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Last modified April 17 16:59 EDT 2021. Contains 343063 sequences. (Running on oeis4.)