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A323041
Numbers k such that 393*2^k+1 is prime.
1
1, 5, 6, 8, 13, 17, 21, 24, 25, 37, 41, 46, 173, 185, 285, 313, 344, 368, 421, 550, 558, 669, 709, 749, 781, 956, 1009, 1141, 1165, 1441, 1461, 1849, 1961, 2070, 2409, 2453, 2658, 2998, 4493, 5737, 6281, 7113, 8488, 8877, 9198, 9777, 10266, 11428, 14200
OFFSET
1,2
LINKS
Jeppe Stig Nielsen, Table of n, a(n) for n = 1..75 (terms n = 1..71 from Robert Price)
Ray Ballinger, Proth Search Page
Ray Ballinger and Wilfrid Keller, List of primes k*2^n + 1 for 300 < k < 600
Eric Weisstein's World of Mathematics, Proth Prime
MAPLE
select(k->isprime(393*2^k+1), [$1..1000]); # Muniru A Asiru, Jan 03 2019
MATHEMATICA
Select[Range[1000], PrimeQ[393*2^# + 1] &]
PROG
(Magma) [n: n in [0.. 4000] | IsPrime(393*2^n+1)]; // Vincenzo Librandi, Jan 04 2019
CROSSREFS
Sequence in context: A331264 A096467 A334120 * A105830 A067527 A105057
KEYWORD
nonn,hard
AUTHOR
Robert Price, Jan 03 2019
STATUS
approved