%I #12 Mar 05 2020 22:28:14
%S 1,2,3,4,40,59,60,61,62,241,276,404,2159,2160,2161
%N Numbers k such that A134303(k) is the lesser of twin primes, A134303(k) = A134304(k).
%o (PARI) a3(n) = {my(k=1); while (!(isprime(k*2^n*(k*2^n-1)-1)), k++); k;}
%o a4(n) = {my(k=1); while (!(isprime(p=k*2^n*(k*2^n-1)-1) && isprime(p+2)), k++); k;}
%o isok(n) = a3(n) == a4(n); \\ _Michel Marcus_, Sep 17 2019
%Y Cf. A134303, A134304.
%K nonn,more
%O 1,2
%A _Pierre CAMI_, Oct 19 2007
%E a(12)-a(15) from _Jinyuan Wang_, Mar 05 2020