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A282669 Prime numbers p > 3 such that 2^p - 9 is prime. 0
5, 11, 17, 251, 563, 21011 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Let W = 2^p - 9 and s = (W+7)/(2*p), then 3^s == 4 (mod W) for terms 1..6.

LINKS

Table of n, a(n) for n=1..6.

PROG

(PARI)

forprime(p=5, 10^5, W= 2^p-9; if(ispseudoprime(W), print1(p, ", ")))

CROSSREFS

Cf. A059610.

Sequence in context: A059960 A265850 A185365 * A271655 A294135 A265851

Adjacent sequences:  A282666 A282667 A282668 * A282670 A282671 A282672

KEYWORD

nonn,more

AUTHOR

Dmitry Ezhov, Mar 07 2017

STATUS

approved

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Last modified November 27 04:07 EST 2020. Contains 338677 sequences. (Running on oeis4.)