If an=3na_n = 3^nan=3n, identify the recurrence relation.
an=3an−1a_n = 3a_{n-1}an=3an−1
an=an−1+3a_n = a_{n-1} + 3an=an−1+3
an=2an−1a_n = 2a_{n-1}an=2an−1
an=3an−2a_n = 3a_{n-2}an=3an−2