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A050855
Numbers n such that 207*2^n-1 is prime.
0
2, 9, 12, 17, 20, 21, 50, 53, 132, 168, 341, 360, 381, 501, 1065, 1169, 1545, 2109, 2520, 2661, 3149, 4077, 11252, 21588, 21692, 39509, 52685, 67196, 87708, 232436, 372312, 417818, 481385, 507833
OFFSET
1,1
COMMENTS
Also in the sequence: 643478 - Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008
PROG
(PARI) is(n)=ispseudoprime(207*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A124742 A152003 A251428 * A031070 A350630 A225547
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