A323107 Numbers k such that 415*2^k+1 is prime.

6, 10, 26, 30, 40, 50, 68, 94, 106, 114, 140, 328, 386, 438, 1540, 1976, 2024, 3944, 3988, 5378, 6068, 6394, 7198, 9040, 10666, 35860, 39884, 119234, 131246, 240190, 315390, 392106, 438776, 675284, 758994, 1055734, 1684046, 1743176, 2549590

Offset

1,1

Links

Table of n, a(n) for n=1..39.

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(415*2^k+1), [$1..1000]); # Muniru A Asiru, Jan 04 2019

Mathematica

Select[Range[1000], PrimeQ[415*2^# + 1] &]

Crossrefs

Sequence in context: A109095 A349692 A351446 * A077621 A298736 A336845

Adjacent sequences: A323104 A323105 A323106 * A323108 A323109 A323110

Keyword

nonn,more,hard

Author

Robert Price, Jan 04 2019

Extensions

a(39) from Jeppe Stig Nielsen, Jan 04 2020

Status

approved