A053353 Numbers k such that 273*2^k + 1 is prime.

1, 2, 5, 10, 13, 40, 41, 45, 56, 64, 72, 86, 94, 121, 160, 213, 338, 352, 833, 1014, 1072, 1098, 1297, 1381, 1952, 1990, 2421, 2600, 3474, 3533, 3602, 4361, 5846, 6234, 6926, 7562, 8238, 10866, 11240, 11765, 26408, 26648, 28258, 53233, 53405, 67344, 73453

Offset

1,2

Links

Jeppe Stig Nielsen, Table of n, a(n) for n = 1..63 (terms n = 1..62 from Robert Price)

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[273*2^# + 1] &] (* G. C. Greubel, May 24 2018 *)

Prog

(PARI) is(n)=ispseudoprime(273*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017
(Magma) [n: n in [1..300] | IsPrime(273*2^n+1)];  // G. C. Greubel, May 24 2018

Crossrefs

Sequence in context: A033316 A099194 A140411 * A099792 A331605 A115757

Adjacent sequences: A053350 A053351 A053352 * A053354 A053355 A053356

Keyword

hard,nonn

Author

N. J. A. Sloane, Dec 29 1999

Extensions

a(48)-a(62) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 20 2018

Status

approved