login
A053358
Numbers k such that 283*2^k + 1 is prime.
0
30, 264, 486, 1950, 3480, 14106, 77394, 472530, 1494614, 2868750
OFFSET
1,1
MATHEMATICA
Select[Range[5*10^3], PrimeQ[283*2^# + 1] &] (* G. C. Greubel, May 24 2018 *)
PROG
(PARI) is(n)=ispseudoprime(283*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017
(Magma) [n: n in [1..5000] | IsPrime(283*2^n+1)]; // G. C. Greubel, May 24 2018
CROSSREFS
Sequence in context: A126525 A230615 A230731 * A163667 A214944 A259455
KEYWORD
hard,nonn,more
AUTHOR
N. J. A. Sloane, Dec 29 1999
EXTENSIONS
a(8)-a(9) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 20 2018
a(10) from Jeppe Stig Nielsen, Jan 19 2020
STATUS
approved