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A050537 Numbers n such that 23*2^n-1 is prime. 0
4, 6, 12, 46, 72, 244, 264, 544, 888, 1146, 14826, 24978, 103386, 323668, 458362, 496422 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..16.

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(23*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Cf. A032361 23*2^n+1 is prime.

Sequence in context: A060202 A062624 A154666 * A114413 A068507 A133454

Adjacent sequences:  A050534 A050535 A050536 * A050538 A050539 A050540

KEYWORD

hard,nonn

AUTHOR

N. J. A. Sloane, Dec 29 1999

EXTENSIONS

More terms from Hugo Pfoertner, Jul 14 2004

More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008

STATUS

approved

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Last modified October 4 21:22 EDT 2022. Contains 357240 sequences. (Running on oeis4.)