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A032366
Numbers k such that 33*2^k+1 is prime.
0
1, 6, 13, 18, 21, 22, 25, 28, 66, 93, 118, 289, 412, 453, 525, 726, 828, 1420, 1630, 3076, 3118, 4452, 4941, 5236, 6346, 9133, 13401, 14214, 18766, 37249, 42685, 47805, 61372, 74178, 600270, 922782, 1130884, 2345001, 3176269, 3570132, 3649810
OFFSET
1,2
COMMENTS
With a(37) = 1130884 the list is complete up to 2.1*10^6, but k = 2345001, 3176269 and 3570132 are also in the sequence, cf. Ballinger & Keller link. - M. F. Hasler, Jul 20 2019
The mentioned limit up to which the list is complete, has reached about 3.7*10^6 (PrimeGrid). - Jeppe Stig Nielsen, Sep 19 2019
LINKS
PROG
(PARI) is(n)=ispseudoprime(33*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Cf. A002240 (33*2^n-1 is prime).
Sequence in context: A197562 A322431 A153696 * A287237 A282975 A094696
KEYWORD
nonn,hard
EXTENSIONS
Added more terms from the Ballinger & Keller page. - Joerg Arndt, Apr 07 2013
Added & edited links & cross-references. - M. F. Hasler, Jul 20 2019
a(38)-a(41) from Jeppe Stig Nielsen, Sep 18 2019
STATUS
approved