A320338 Numbers k such that 481*2^k+1 is prime.

64, 196, 2164, 2956, 110748, 1263444, 1593660, 2201148

Offset

1,1

Links

Table of n, a(n) for n=1..8.

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[481*2^# + 1] &]

Crossrefs

Sequence in context: A175166 A220763 A030028 * A250135 A273321 A091077

Adjacent sequences: A320335 A320336 A320337 * A320339 A320340 A320341

Keyword

nonn,more,hard

Author

Robert Price, Jan 07 2019

Extensions

a(8) from Jeppe Stig Nielsen, Feb 25 2020

Status

approved