%I #6 Sep 17 2019 10:31:51
%S 2,1,2,1,11,21,57,211,141,156,78,39,140,70,35,214,107,90,45,309,330,
%T 165,120,60,30,15,435,651,420,210,105,429,1143,576,288,144,72,36,18,9,
%U 116,58,29,2286,1143,1638,819,1071,983,1983
%N Least k such that k*2^n*(k*2^n-1)-1 and k*2^n*(k*2^n-1)+1 are twin primes.
%o (PARI) a(n) = {my(k=1); while (!(isprime(p=k*2^n*(k*2^n-1)-1) && isprime(p+2)), k++); k;} \\ _Michel Marcus_, Sep 17 2019
%Y Cf. A134303, A134305.
%K nonn
%O 1,1
%A _Pierre CAMI_, Oct 19 2007
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