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A032467
Numbers k such that 181*2^k+1 is prime.
0
4, 8, 32, 200, 272, 416, 484, 788, 3560, 6628, 44392, 64264, 75832, 80440, 94112, 315104, 359404, 428576, 608192, 1209572
OFFSET
1,1
MAPLE
select(k->isprime(181*2^k+1), [$0..1000]); # Muniru A Asiru, Dec 18 2018
MATHEMATICA
Select[Range[1000], PrimeQ[181*2^# + 1] & ] (* Robert Price, Dec 18 2018 *)
PROG
(PARI) is(n)=ispseudoprime(181*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A261196 A222537 A208924 * A009265 A173326 A173652
KEYWORD
nonn,hard,more
AUTHOR
EXTENSIONS
a(16)-a(20) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 18 2018
STATUS
approved