If a sequence is defined by an=4an−1a_n = 4 a_{n-1}an=4an−1 with a0=3a_0 = 3a0=3, what is ana_nan in closed form?
an=4⋅3na_n = 4 \cdot 3^nan=4⋅3n
an=3+4na_n = 3 + 4nan=3+4n
an=12na_n = 12^nan=12n
an=3⋅4na_n = 3 \cdot 4^nan=3⋅4n