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A249509
Smallest number k >= A000043(n) such that k*A000668(n)*(k*A000668(n)+1)-1 is prime.
0
2, 3, 5, 7, 25, 19, 20, 42, 96, 190, 134, 164, 650, 852, 1455, 2765, 2480, 3960, 5464, 6694, 17206, 13118, 13680, 28481, 27445, 28821, 101696, 116232, 142083, 187376, 250118, 1200007
OFFSET
1,1
COMMENTS
a(34) = 1200007.
A000043(34) = 756839.
A000668(34) = 2^756839-1.
1200007*(2^756839-1)*(1200007*(2^756839-1)+1)-1 is a 455675 digits certified prime using PFGW.
LINKS
Chris K. Caldwell, The List of Largest Known Primes, Prime corresponding to a(34)
CROSSREFS
KEYWORD
nonn
AUTHOR
Pierre CAMI, Oct 30 2014
STATUS
approved