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A032470
Numbers k such that 187*2^k+1 is prime.
0
6, 12, 48, 82, 126, 186, 732, 1926, 2802, 6712, 10026, 16062, 17790, 18156, 67878, 176316, 194950, 231112, 239832, 494602, 497926, 693012, 788640, 2249974
OFFSET
1,1
MAPLE
select(k->isprime(187*2^k+1), [$0..1000]); # Muniru A Asiru, Dec 18 2018
MATHEMATICA
Select[Range[1000], PrimeQ[187*2^# + 1] & ] (* Robert Price, Dec 18 2018 *)
PROG
(PARI) is(n)=ispseudoprime(187*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A105863 A052904 A106692 * A342302 A018809 A226882
KEYWORD
nonn,hard,more
AUTHOR
EXTENSIONS
a(16)-a(23) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 18 2018
a(24) from Jeppe Stig Nielsen, Apr 19 2020
STATUS
approved