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 A032424 Numbers k such that 149*2^k+1 is prime. 0
 3, 7, 9, 15, 17, 27, 33, 35, 57, 125, 127, 137, 191, 513, 819, 827, 921, 931, 1047, 1147, 1599, 1815, 2499, 2995, 8151, 11403, 22783, 29841, 30201, 85935, 142281, 149831, 184457, 221595, 256099, 283881, 333933, 483045, 658917, 714199, 812719, 1295061, 1561951 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The subsequence of prime values starts 3, 7, 17, 127, 137, 191, 827, 22783, 714199, ... - Muniru A Asiru, Apr 29 2019 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 MAPLE select(k->isprime(149*2^k+1), [\$0..1000])[]; # Muniru A Asiru, Dec 18 2018 MATHEMATICA Select[Range[1000], PrimeQ[149*2^# + 1] & ] (* Robert Price, Dec 18 2018 *) PROG (PARI) is(n)=ispseudoprime(149*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017 CROSSREFS Sequence in context: A178207 A210532 A110872 * A280861 A287264 A187108 Adjacent sequences:  A032421 A032422 A032423 * A032425 A032426 A032427 KEYWORD nonn,more AUTHOR EXTENSIONS Extended by Hugo Pfoertner, Jul 02 2003 a(33)-a(43) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 18 2018 STATUS approved

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Last modified December 7 20:40 EST 2021. Contains 349589 sequences. (Running on oeis4.)