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

Offset

1,2

Links

Table of n, a(n) for n=1..27.

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

Status

approved