A050847 - OEIS

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A050847

Numbers n such that 191*2^n-1 is prime.

0

226, 3594, 59770, 240802

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Table of n, a(n) for n=1..4.

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(191*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A251395 A251507 A251500 * A098247 A092994 A031513

Adjacent sequences: A050844 A050845 A050846 * A050848 A050849 A050850

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