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A050572 Numbers n such that 93*2^n-1 is prime. 0
3, 4, 7, 10, 15, 18, 19, 24, 27, 39, 60, 84, 111, 171, 192, 222, 639, 954, 2400, 2587, 4012, 4359, 5250, 6012, 6183, 7344, 10603, 12403, 13215, 29154, 78192, 81294, 103744, 107991, 174412, 176479, 203728, 205158, 251199, 362268, 580482 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

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(93*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A296994 A236475 A287458 * A249668 A105343 A237834

Adjacent sequences:  A050569 A050570 A050571 * A050573 A050574 A050575

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 7 05:14 EST 2019. Contains 329839 sequences. (Running on oeis4.)