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A050596 Numbers n such that 141*2^n-1 is prime. 0
1, 2, 7, 10, 11, 13, 38, 46, 61, 170, 299, 445, 815, 983, 4237, 6146, 7255, 7459, 7585, 8411, 8647, 14855, 20338, 21671, 29293, 89318, 92498, 98686, 121142, 250271, 619742 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..31.

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(141*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A043357 A023730 A045281 * A045266 A108493 A069494

Adjacent sequences:  A050593 A050594 A050595 * A050597 A050598 A050599

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 24 07:28 EDT 2020. Contains 337317 sequences. (Running on oeis4.)