A323105 Numbers k such that 411*2^k+1 is prime.

1, 4, 7, 19, 37, 55, 72, 79, 81, 136, 139, 955, 976, 979, 1537, 1579, 2292, 3277, 4644, 6007, 6391, 6805, 17959, 25999, 58327, 60919, 112957, 117781, 130204, 181176, 192637, 459595, 793944, 1078339, 1677196, 1861627, 2115559

Offset

1,2

Links

Table of n, a(n) for n=1..37.

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

Maple

select(k->isprime(411*2^k+1), [$1..1000]); # Muniru A Asiru, Jan 04 2019

Mathematica

Select[Range[1000], PrimeQ[411*2^# + 1] &]

Crossrefs

Sequence in context: A291596 A323655 A062306 * A006130 A140167 A182228

Adjacent sequences: A323102 A323103 A323104 * A323106 A323107 A323108

Keyword

nonn,more,hard

Author

Robert Price, Jan 04 2019

Extensions

a(37) from Jeppe Stig Nielsen, May 30 2020

Status

approved