A322959 Numbers k such that 333*2^k+1 is prime.

5, 6, 9, 18, 25, 33, 50, 54, 69, 70, 101, 153, 176, 245, 401, 448, 745, 768, 806, 840, 1338, 1718, 3504, 4164, 5581, 5729, 6010, 6705, 8076, 10233, 12169, 13345, 55285, 58138, 113589, 197820, 203453, 238130, 364946, 817201, 1068320, 1708106, 1837105

Offset: 1

Author

Robert Price, Dec 31 2018

Keywords

• nonn
• more
• hard

Links

• 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

Crossrefs

Cf. A002255, A050527.

Programs

Maple

select(n->isprime(333*2^n+1),[$1..1000]); # Muniru A Asiru, Dec 31 2018

Mathematica

Select[Range[1000], PrimeQ[333*2^# + 1] &] (* Robert Price, Dec 31 2018 *)