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A297674 Greater of twin primes p such that 2^p-1 is prime. 0

%I

%S 5,7,13,19,31,61,1279,4423,110503,132049,20996011,24036583

%N Greater of twin primes p such that 2^p-1 is prime.

%C Also 74207281 is a member, but its position is not known yet.

%o (PARI) is(n) = isprime(n)&&isprime(n-2)&&ispseudoprime(2^n-1)

%Y Intersection of A000043 and A006512.

%Y Cf. A087858.

%K nonn,hard,more

%O 1,1

%A _Jeppe Stig Nielsen_, Jan 03 2018

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Last modified June 16 09:57 EDT 2021. Contains 345056 sequences. (Running on oeis4.)