Solve the recurrence relation an−6an−1+9an−2=0a_n - 6a_{n-1} + 9a_{n-2} = 0an−6an−1+9an−2=0 with initial conditions a0=1a_0 = 1a0=1 and a1=9a_1 = 9a1=9. What is a3a_3a3?
81
135
189
243