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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 (list; graph; refs; listen; history; text; internal format)
 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 Ray Ballinger, Proth Search Page Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300. (Created April 1998, updated July 2019.) Chris K. Caldwell, The Prime Database: 33*2^3649810+1. M. B. Porter et al, Factors of 33*2^n+1, OEIS wiki, updated July 2019 PrimeGrid, Fermat Divisor Search range statistics. 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 Adjacent sequences:  A032363 A032364 A032365 * A032367 A032368 A032369 KEYWORD nonn,hard AUTHOR 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

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Last modified June 25 09:45 EDT 2021. Contains 345453 sequences. (Running on oeis4.)