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A050892
Numbers k such that 267*2^k-1 is prime.
0
4, 5, 8, 14, 16, 17, 20, 26, 28, 34, 40, 44, 53, 58, 74, 80, 86, 94, 128, 130, 140, 149, 178, 365, 448, 878, 920, 1217, 2417, 3400, 3725, 3934, 4454, 5276, 7360, 9544, 11860, 16270, 32038, 37468, 116537, 117358, 119006, 147838, 198536, 211358, 216137, 238670, 287537
OFFSET
1,1
MATHEMATICA
Select[Range[1000], PrimeQ[267*2^# - 1] & ] (* Robert Price, Dec 29 2018 *)
PROG
(PARI) is(n)=ispseudoprime(267*2^n-1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A019526 A242014 A145488 * A347880 A274167 A145265
KEYWORD
hard,nonn
AUTHOR
N. J. A. Sloane, Dec 29 1999
EXTENSIONS
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008
a(48)-a(49) from the Wilfrid Keller link by Robert Price, Dec 29 2018
STATUS
approved