A032419 Numbers k such that 139*2^k + 1 is prime.
2, 14, 914, 12614, 335522, 1567874
Offset: 1
Links
- Ray Ballinger, Proth Search Page
- Ray Ballinger & Wilfrid Keller, List of primes k.2^n + 1 for k < 300.
- Y. Gallot, Proth.exe: Windows Program for Finding Large Primes
- Wilfrid Keller, List of primes k.2^n - 1 for k < 300
- Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime
Programs
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Maple
select(k->isprime(139*2^k+1),[$0..1000])[]; # Muniru A Asiru, Dec 18 2018
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Mathematica
Select[Range[1000], PrimeQ[139*2^# + 1] & ] (* Robert Price, Dec 18 2018 *)
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PARI
is(n)=ispseudoprime(139*2^n+1) \\ Charles R Greathouse IV, Jun 07 2017
Extensions
One more term (from the Ballinger-Keller web page) from M. F. Hasler, Apr 18 2007
a(6) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 18 2018