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Consider primes p and q such that p = 3^k + 14 and q = 3^(k+1) + 14 for some k; sequence gives values of p.
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%I #11 Jul 16 2015 21:45:43

%S 17,23,257,19697

%N Consider primes p and q such that p = 3^k + 14 and q = 3^(k+1) + 14 for some k; sequence gives values of p.

%C There are no additional terms up to k=2000, which generates a 955-digit nonprime candidate number for p. - _Harvey P. Dale_, Aug 17 2014

%e 3^1 + 14 = 17, 3^2 + 14 = 23.

%t Transpose[Select[Table[{3^k+14,3^(k+1)+14},{k,10}],AllTrue[ #,PrimeQ]&]] [[1]] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Aug 17 2014 *)

%o (PARI) g(m,n,b) = { for(x=0,n, y=m+b^x+b%2; z=m+b^(x+1)+b%2; if(isprime(y)&isprime(z),print1(y",") ) ) }

%K nonn

%O 0,1

%A _Cino Hilliard_, Jun 29 2005