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A323114
Numbers k such that 427*2^k+1 is prime.
1
2, 4, 6, 8, 12, 20, 22, 56, 66, 94, 136, 142, 174, 186, 200, 286, 352, 362, 512, 582, 842, 1056, 1080, 1144, 1242, 1810, 4802, 5106, 6914, 12982, 16760, 19958, 20108, 22194, 23512, 29636, 42816, 66178, 70624, 81390, 129958, 184046, 278876, 343432, 396612
OFFSET
1,1
Jeppe Stig Nielsen, Table of n, a(n) for n = 1..57 (terms n = 1..54 from Robert Price)
Ray Ballinger, Proth Search Page
Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for 300 < k < 600
Eric Weisstein's World of Mathematics, Proth Prime
MAPLE
select(k->isprime(427*2^k+1), [\$1..1000]); # Muniru A Asiru, Jan 05 2019
MATHEMATICA
Select[Range[1000], PrimeQ[427*2^# + 1] &]
PROG
(Python)
from sympy.ntheory.primetest import isprime
for n in range(1, 1000):
if isprime(427*2**n+1):
print(n, end=', ') # Stefano Spezia, Jan 05 2019
CROSSREFS
Sequence in context: A057335 A126907 A292994 * A362231 A118563 A228515
KEYWORD
nonn,hard
AUTHOR
Robert Price, Jan 04 2019
STATUS
approved

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Last modified September 19 23:07 EDT 2024. Contains 376015 sequences. (Running on oeis4.)