Consider a sequence defined by an=an−1+2an−2a_n = a_{n-1} + 2a_{n-2}an=an−1+2an−2 with a0=1,a1=1a_0 = 1, a_1 = 1a0=1,a1=1. What is the value of a3a_3a3?
333
555
444
777