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A050866 Numbers n such that 229*2^n-1 is prime. 0
1, 3, 7, 19, 25, 27, 71, 97, 231, 235, 291, 295, 313, 347, 491, 511, 531, 571, 803, 1499, 1523, 1607, 1743, 2161, 2231, 3113, 5511, 5863, 6039, 8055, 8443, 9707, 12155, 12195, 21049, 24271, 34403, 34879, 56491, 58839, 162583, 207863, 220147, 560259 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..44.

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(229*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A205302 A127925 A032388 * A226923 A001985 A203321

Adjacent sequences:  A050863 A050864 A050865 * A050867 A050868 A050869

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 June 20 05:01 EDT 2019. Contains 324229 sequences. (Running on oeis4.)