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A129221
Residues of the Lucas - Lehmer primality test for M(13) = 8191.
8
4, 14, 194, 4870, 3953, 5970, 1857, 36, 1294, 3470, 128, 0
OFFSET
0,1
COMMENTS
Since a(11) = 0, M(13) = 8191 is prime.
LINKS
Eric Weisstein's World of Mathematics, Lucas Lehmer Test.
FORMULA
a(0) = 4 a(n) = a(n-1)^2 mod 2^p-1 Last term: a(p-2)
EXAMPLE
a(11)= 128^2 - 2 mod 8191 = 16382 mod 8191 = 0
KEYWORD
fini,full,nonn
AUTHOR
Sergio Pimentel, Apr 04 2007
STATUS
approved