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A050861 Numbers n such that 219*2^n-1 is prime. 0
7, 81, 381, 412, 657, 853, 1317, 3261, 3768, 6081, 14017, 19993, 25863, 31801, 40113, 48877, 558313 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300
PROG
(PARI) is(n)=ispseudoprime(219*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A058785 A373441 A171768 * A083226 A088735 A364322
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 June 25 15:24 EDT 2024. Contains 373705 sequences. (Running on oeis4.)