A053349 Numbers k such that 265*2^k + 1 is prime.

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

Offset

1,1

Links

Table of n, a(n) for n=1..36.

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[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