A053359 Numbers k such that 285*2^k + 1 is prime.

1, 3, 4, 15, 18, 21, 27, 37, 45, 55, 58, 69, 73, 87, 171, 201, 232, 307, 375, 567, 882, 2869, 3364, 4071, 4825, 15328, 20341, 26641, 36703, 57291, 62973, 67347, 141253, 155637, 165957, 230629, 295791, 343144, 372841, 454378, 604747, 690973, 736084, 852381

Offset

1,2

Links

Jeppe Stig Nielsen, Table of n, a(n) for n = 1..47

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

Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime

Mathematica

Select[Range[5*10^3], PrimeQ[285*2^# + 1] &] (* G. C. Greubel, May 25 2018 *)

Prog

(PARI) is(n)=ispseudoprime(285*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017
(Magma) [n: n in [1..300] | IsPrime(285*2^n+1)];  // G. C. Greubel, May 25 2018

Crossrefs

Sequence in context: A341779 A136641 A325186 * A056742 A338123 A041435

Adjacent sequences: A053356 A053357 A053358 * A053360 A053361 A053362

Keyword

hard,nonn

Author

N. J. A. Sloane, Dec 29 1999

Extensions

a(34)-a(46) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 22 2018

Terms moved from Data section to b-file, and additional term appended to b-file, by Jeppe Stig Nielsen, May 31 2020

Status

approved