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A050893 Numbers n such that 269*2^n-1 is prime. 0
8, 24, 272, 2304, 3840, 3848, 58748, 63992, 104768, 264932, 628904 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..11.

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(269*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A094061 A182589 A002268 * A037025 A105063 A166483

Adjacent sequences:  A050890 A050891 A050892 * A050894 A050895 A050896

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 May 7 12:38 EDT 2021. Contains 343650 sequences. (Running on oeis4.)