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%I #5 Mar 30 2012 17:26:52
%S 12,60,300,3000,30000,300000,3000000,30000000,300000000,3000000000,
%T 30000000000,300000000000,3000000000000,30000000000000,
%U 300000000000000,3000000000000000,30000000000000000,300000000000000000,3000000000000000000
%N Length of the cycle for Lucas numbers mod 10^n.
%C This is the length of the cycle for final n decimal digits in Lucas numbers (A000032)
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/LucasNumber.html">Lucas Number</a>
%F a(1)=12, a(2)=60, a(n)=3*10^(n-1) for n>2.
%F a(n)=lcm(3*2^(n-1),4*5^(n-1)). In particular, for n>=3, a(n) = 3*10^(n-1). - _Max Alekseyev_, May 17 2006
%e L(i) mod 10 = L(i+12) mod 10; L(i) mod 10^2 = L(i+a(2)) mod 10^2; L(i) mod 10^3 = L(i+a(3)) mod 10^3;
%Y Cf. A000032, A096363, A001175.
%K easy,nonn
%O 1,1
%A Jerzy Podgorski (j.podgorski(AT)pollub.pl), May 14 2006; corrected May 16 2006
%E More terms from _Max Alekseyev_, May 17 2006
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