A sequence is defined by an=2an−1−2an−2a_n = 2a_{n-1} - 2a_{n-2}an=2an−1−2an−2 with a0=1a_0 = 1a0=1 and a1=1a_1 = 1a1=1. What is the value of a8a_8a8?
-16
16
-8
8