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 A032506 Numbers k such that 259*2^k+1 is prime. 0
 38, 70, 3230, 62918, 82878, 1282582 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Ray Ballinger, Proth Search Page Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300 Wilfrid Keller, List of primes k.2^n - 1 for k < 300 MATHEMATICA Select[Range[1000], PrimeQ[259*2^# + 1] & ] (* Robert Price, Dec 20 2018 *) PROG (PARI) is(n)=ispseudoprime(259*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017 CROSSREFS Sequence in context: A343974 A335483 A071885 * A044104 A044485 A160846 Adjacent sequences: A032503 A032504 A032505 * A032507 A032508 A032509 KEYWORD hard,nonn,more AUTHOR EXTENSIONS a(6) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 20 2018 STATUS approved

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Last modified December 1 08:58 EST 2022. Contains 358467 sequences. (Running on oeis4.)