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A050553
Numbers n such that 55*2^n-1 is prime.
0
1, 3, 5, 7, 15, 33, 41, 57, 69, 75, 77, 131, 133, 153, 247, 305, 351, 409, 471, 1251, 1259, 2253, 2411, 2425, 2699, 3221, 4099, 4173, 4291, 4905, 5349, 6723, 7143, 7505, 10539, 10557, 12099, 17373, 23721, 27895, 33801, 35519, 45927, 63589, 73287, 96933, 106659, 218043, 253047, 397941, 651015
OFFSET
1,2
PROG
(PARI) is(n)=ispseudoprime(55*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Cf. A057813.
Sequence in context: A303027 A217615 A334084 * A005540 A155802 A080741
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