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A309854
Numbers k such that 2*k^5 - 1 is prime.
2
6, 7, 10, 12, 15, 22, 34, 46, 57, 60, 64, 75, 81, 82, 84, 94, 112, 117, 129, 132, 151, 160, 169, 171, 175, 186, 196, 210, 214, 222, 225, 255, 264, 292, 301, 309, 315, 330, 357, 364, 369, 370, 379, 381, 384, 400, 412, 417, 426, 430, 454, 474, 516, 547, 549, 582, 610, 631, 636, 655
OFFSET
1,1
LINKS
MAPLE
filter:= k -> isprime(2*k^5-1):
select(filter, [$1..1000]); # Robert Israel, Oct 29 2023
PROG
(PARI) isok(k) = isprime(2*k^5 - 1); \\ Michel Marcus, Jul 22 2021
CROSSREFS
Cf. A214289 (2*k^3 - 1 prime), A182783 (2*k^4 - 1 prime), A309855 (subset of primes).
Sequence in context: A374353 A037303 A135121 * A083133 A101972 A102727
KEYWORD
nonn
AUTHOR
R. J. Mathar, Aug 20 2019
STATUS
approved