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A050569 Numbers n such that 87*2^n-1 is prime. 0
1, 2, 8, 9, 10, 12, 22, 29, 32, 50, 57, 69, 81, 122, 138, 200, 296, 514, 656, 682, 778, 881, 1422, 1494, 1857, 3060, 3489, 4106, 5129, 5378, 8096, 8546, 10138, 10941, 13749, 21758, 23554, 24582, 27526, 28581, 29306, 29588, 36101, 36681, 41378, 45689, 55769, 56049, 65676, 77361, 96426, 110189, 128630, 142738, 154352, 155794, 188689, 353734, 360829, 382268, 796341, 942790 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..62.

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(87*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A001560 A175463 A167450 * A318175 A318182 A047469

Adjacent sequences:  A050566 A050567 A050568 * A050570 A050571 A050572

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 April 1 14:52 EDT 2020. Contains 333163 sequences. (Running on oeis4.)