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A322952
Numbers k such that 321*2^k+1 is prime.
0
1, 5, 32, 68, 109, 128, 133, 212, 241, 653, 776, 1339, 1787, 2659, 6388, 6547, 8365, 16699, 62861, 64795, 83227, 195376, 278875, 442480, 542876, 730321, 1168576, 1257859, 1629307, 4715725
OFFSET
1,2
MAPLE
select(n->isprime(321*2^n+1), [$1..1000]); # Muniru A Asiru, Dec 31 2018
MATHEMATICA
Select[Range[1000], PrimeQ[321*2^# + 1] &] (* Robert Price, Dec 31 2018 *)
CROSSREFS
Sequence in context: A140154 A350997 A073694 * A101966 A341423 A184536
KEYWORD
nonn,more,hard,changed
AUTHOR
Robert Price, Dec 31 2018
EXTENSIONS
a(30) from Jeppe Stig Nielsen, Dec 20 2024
STATUS
approved