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 A053349 Numbers k such that 265*2^k + 1 is prime. 0
 2, 4, 16, 58, 70, 80, 158, 202, 322, 356, 616, 2152, 3136, 3308, 3626, 5930, 6046, 8930, 9100, 10046, 10142, 16696, 17996, 23318, 25900, 39934, 63794, 69260, 300632, 302248, 307132, 311924, 451724, 1155950, 1639448, 1745450 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS 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[5*10^3], PrimeQ[265*2^# + 1] &] (* G. C. Greubel, May 24 2018 *) PROG (PARI) is(n)=ispseudoprime(265*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017 (MAGMA) [n: n in [1..300] | IsPrime(265*2^n+1)];  // G. C. Greubel, May 24 2018 CROSSREFS Sequence in context: A232664 A153954 A275764 * A228626 A152876 A153963 Adjacent sequences:  A053346 A053347 A053348 * A053350 A053351 A053352 KEYWORD hard,nonn,more AUTHOR N. J. A. Sloane, Dec 29 1999 EXTENSIONS a(29)-a(36) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 20 2018 STATUS approved

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Last modified December 8 11:31 EST 2021. Contains 349596 sequences. (Running on oeis4.)