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%I #13 Oct 29 2014 04:02:00
%S 29,47,101,263,6581,177167
%N Consider primes p and q such that p = 3^k + 20 and q = 3^(k+1) + 20 for some k; sequence gives values of q.
%e 3^1 + 20 = 23, 3^2 + 20 = 29.
%t Transpose[Select[Partition[#+20&/@(3^Range[50]),2,1],AllTrue[ #,PrimeQ]&]] [[2]] (* The program uses the function AllTrue from Mathematica version 10 *) (* _Harvey P. Dale_, Oct 29 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(z",") ) ) }
%Y Cf. A108249.
%K nonn
%O 1,1
%A _Cino Hilliard_, Jun 29 2005
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