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A050580 Numbers n such that 109*2^n-1 is prime. 0
9, 149, 177, 419, 617, 1799, 3227, 6017, 12957, 141227 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..10.

Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300

Wilfrid Keller, List of primes k.2^n - 1 for k < 300

Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime

Kosmaj, Riesel list k<300.

PROG

(PARI) is(n)=ispseudoprime(109*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A211106 A006691 A304312 * A266128 A183439 A296017

Adjacent sequences:  A050577 A050578 A050579 * A050581 A050582 A050583

KEYWORD

hard,nonn

AUTHOR

N. J. A. Sloane, Dec 29 1999

EXTENSIONS

More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008

STATUS

approved

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Last modified December 2 18:11 EST 2021. Contains 349445 sequences. (Running on oeis4.)