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A050884
Numbers n such that 251*2^n-1 is prime.
0
6, 110, 1302, 4598, 74030, 359790
OFFSET
1,1
PROG
(PARI) is(n)=ispseudoprime(251*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A217987 A119814 A227443 * A156554 A197325 A197978
KEYWORD
hard,nonn
AUTHOR
N. J. A. Sloane, Dec 29 1999
EXTENSIONS
359790 from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008
STATUS
approved