A323004 Numbers k such that 359*2^k+1 is prime.

1, 5, 7, 9, 47, 55, 65, 69, 97, 103, 273, 1231, 1721, 2277, 3981, 4125, 4569, 5135, 8327, 8593, 24249, 37609, 396617, 633247, 920709, 2165551, 2870935, 4578161

Offset

1,2

Links

Table of n, a(n) for n=1..28.

Ray Ballinger, Proth Search Page

Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for 300 < k < 600

Y. Gallot, Proth.exe: Windows Program for Finding Large Primes

Wilfrid Keller, List of primes k.2^n - 1 for k < 300

Eric Weisstein's World of Mathematics, Proth Prime

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

Mathematica

Select[Range[1000], PrimeQ[359*2^# + 1] &] (* Robert Price, Jan 01 2019 *)

Crossrefs

Sequence in context: A050113 A050888 A366312 * A264349 A320114 A364284

Adjacent sequences: A323001 A323002 A323003 * A323005 A323006 A323007

Keyword

nonn,more,hard

Author

Robert Price, Jan 01 2019

Extensions

a(26) from Jeppe Stig Nielsen, Apr 19 2020

a(27) from Jeppe Stig Nielsen, Aug 05 2020

a(28) from Jeppe Stig Nielsen, Dec 20 2024

Status

approved