A319488 Numbers k such that 479*2^k+1 is prime.

3, 5, 21, 45, 123, 209, 297, 401, 489, 761, 3159, 4023, 5321, 5907, 7041, 10407, 10491, 11477, 11577, 12471, 12651, 24353, 78905, 122561, 205385, 280713, 336651, 2209541

Offset

1,1

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[479*2^# + 1] &]

Crossrefs

Sequence in context: A148553 A239795 A261272 * A110026 A235136 A153862

Adjacent sequences: A319485 A319486 A319487 * A319489 A319490 A319491

Keyword

nonn,more,hard

Author

Robert Price, Jan 07 2019

Extensions

a(28) from Jeppe Stig Nielsen, Feb 25 2020

Status

approved