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%I #15 Oct 11 2019 14:39:57
%S 4,14,194,788,701,119,1877,240,282,1736
%N Residues of the Lucas - Lehmer primality test for M(11) = 2047.
%C Since a(9) > 0, M(11) is composite. In fact, 2047 = 23 * 89
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Lucas-LehmerTest.html">Lucas Lehmer Test</a>.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Lucas-Lehmer_primality_test">Lucas Lehmer Primality Test</a>.
%F a(0) = 4; a(n) = a(n-1)^2-2 mod 2^p-1. Last term: a(p-2).
%e a(9) = a(8)^2 - 2 mod 2047 = 282^2 - 2 mod 2047 = 1736.
%Y Cf. A095847, A003010, A129218, A129219, A129221, A129222, A129223, A129224, A129225, A129226, A001348.
%K fini,full,nonn
%O 0,1
%A _Sergio Pimentel_, Apr 05 2007
%E Offset corrected by _Nathaniel Johnston_, May 31 2011