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A323193
Numbers k such that 447*2^k+1 is prime.
1
2, 16, 19, 20, 23, 50, 52, 71, 116, 286, 379, 391, 395, 410, 454, 476, 700, 716, 1340, 1442, 1712, 1996, 2231, 2396, 2783, 2959, 4124, 4466, 7424, 8186, 9542, 10523, 12959, 14803, 19136, 23011, 27032, 33091, 35276, 35302, 36052, 39139, 81736, 125815, 167695
OFFSET
1,1
LINKS
Jeppe Stig Nielsen, Table of n, a(n) for n = 1..54 (terms n = 1..53 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
MATHEMATICA
Select[Range[1000], PrimeQ[447*2^# + 1] &]
CROSSREFS
Sequence in context: A101075 A022370 A161802 * A050850 A082475 A333998
KEYWORD
nonn,hard
AUTHOR
Robert Price, Jan 06 2019
STATUS
approved