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A032414
Numbers k such that 129*2^k+1 is prime.
0
3, 5, 21, 27, 59, 75, 111, 287, 414, 786, 966, 1071, 2433, 2817, 3165, 4958, 5895, 12450, 39399, 50019, 57386, 72599, 75866, 82026, 112497, 268271, 284975, 478538, 564990, 630843, 739023, 851306, 872765, 1774709, 1956915, 2255199
OFFSET
1,1
MATHEMATICA
Select[Range[1000], PrimeQ[129*2^# + 1] & ] (* Robert Price, Dec 17 2018 *)
PROG
(PARI) is(n)=ispseudoprime(129*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A086175 A065926 A128561 * A062225 A288152 A082699
KEYWORD
nonn,more
EXTENSIONS
Extended by Hugo Pfoertner, Jul 02 2003
a(26)-a(35) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 17 2018
a(36) from Jeppe Stig Nielsen, Apr 19 2020
STATUS
approved