The Lucas sequence is the sequence 1, 3, 4, 7, 11,... where the first term is 1, the second term is 3 and each term after that is the sum of the previous two terms. What is the remainder when the $100^{th}$ term of the sequence is divided by $9$?
n=100; a=((1+2#5)/2)^n + ((1-2#5)/2)^n
L(100) ==792,070,839,848,372,253,127 mod 9 ==7 - the remainder
