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A323104
Numbers k such that 409*2^k+1 is prime.
0
2, 6, 18, 110, 186, 318, 398, 1922, 3290, 4346, 5042, 6638, 8306, 59066, 66758, 182198, 214406, 260810, 709350, 947018, 1384346, 1546542, 2360166
OFFSET
1,1
MAPLE
select(k->isprime(409*2^k+1), [$1..1000]); # Muniru A Asiru, Jan 04 2019
MATHEMATICA
Select[Range[1000], PrimeQ[409*2^# + 1] &]
CROSSREFS
Sequence in context: A347727 A308549 A212653 * A376932 A208456 A056743
KEYWORD
nonn,more,hard
AUTHOR
Robert Price, Jan 04 2019
EXTENSIONS
a(23) from Jeppe Stig Nielsen, Dec 18 2024
STATUS
approved