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A050898 Numbers n such that 279*2^n-1 is prime. 0
1, 4, 12, 29, 35, 56, 77, 93, 209, 221, 412, 441, 460, 899, 1859, 1896, 2504, 5315, 6520, 9324, 9460, 11336, 11760, 12317, 21080, 25029, 27064, 29236, 35396, 42791, 55851, 57752, 61551, 73272, 117820, 123253, 162705, 201152, 277455, 318317, 455704 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..41.

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(279*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A121312 A091521 A329483 * A009845 A014342 A086274

Adjacent sequences:  A050895 A050896 A050897 * A050899 A050900 A050901

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 July 8 18:55 EDT 2020. Contains 335524 sequences. (Running on oeis4.)