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A050592 Numbers n such that 133*2^n-1 is prime. 0
3, 11, 15, 19, 31, 59, 75, 103, 163, 235, 375, 615, 767, 1223, 1411, 26655, 47351, 75027, 83323, 121571, 238163, 312359, 359915, 471455 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..24.

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(133*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A106374 A075330 A131323 * A032466 A060698 A294690

Adjacent sequences:  A050589 A050590 A050591 * A050593 A050594 A050595

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 September 30 05:03 EDT 2020. Contains 337435 sequences. (Running on oeis4.)