A323106 Numbers k such that 413*2^k+1 is prime.

1, 5, 9, 13, 25, 85, 113, 133, 185, 217, 269, 285, 469, 1025, 2289, 4849, 5681, 8489, 12937, 18485, 18809, 20189, 34361, 40509, 41593, 44181, 46517, 68681, 130421, 186893, 187937, 255137, 457801, 469901, 970353, 1387625, 2043829

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(413*2^k+1), [$1..1000]); # Muniru A Asiru, Jan 04 2019

Mathematica

Select[Range[1000], PrimeQ[413*2^# + 1] &]

Crossrefs

Sequence in context: A151895 A267190 A170896 * A257171 A233973 A089977

Adjacent sequences: A323103 A323104 A323105 * A323107 A323108 A323109

Keyword

nonn,more,hard

Author

Robert Price, Jan 04 2019

Extensions

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

Status

approved