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A323102
Numbers k such that 405*2^k+1 is prime.
0
1, 2, 4, 8, 10, 14, 32, 43, 46, 58, 80, 163, 184, 227, 262, 361, 592, 602, 623, 638, 2287, 2680, 3674, 11221, 12278, 12556, 12763, 15412, 21472, 49118, 57040, 64825, 121262, 127495, 300604, 572623, 769828, 904000, 1693765, 2099716
OFFSET
1,2
MAPLE
select(k->isprime(405*2^k+1), [$1..1000]); # Muniru A Asiru, Jan 04 2019
MATHEMATICA
Select[Range[1000], PrimeQ[405*2^# + 1] &]
CROSSREFS
Sequence in context: A049422 A178215 A067925 * A331627 A102431 A076919
KEYWORD
nonn,more,hard
AUTHOR
Robert Price, Jan 04 2019
EXTENSIONS
a(40) from Jeppe Stig Nielsen, May 30 2020
STATUS
approved