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A297674 Greater of twin primes p such that 2^p-1 is prime. 0
5, 7, 13, 19, 31, 61, 1279, 4423, 110503, 132049, 20996011, 24036583 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

LINKS

Table of n, a(n) for n=1..12.

PROG

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

CROSSREFS

Intersection of A000043 and A006512.

Cf. A087858.

Sequence in context: A074304 A264865 A293712 * A072677 A117249 A063910

Adjacent sequences:  A297671 A297672 A297673 * A297675 A297676 A297677

KEYWORD

nonn,hard,more

AUTHOR

Jeppe Stig Nielsen, Jan 03 2018

STATUS

approved

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Last modified May 12 07:28 EDT 2021. Contains 343821 sequences. (Running on oeis4.)