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Numbers k such that A134303(k) is the lesser of twin primes, A134303(k) = A134304(k).
2

%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