Which recurrence relation is linear and homogeneous?
an=an−1+2a_n = a_{n-1} + 2an=an−1+2
an=an−12a_n = a_{n-1}^2an=an−12
an=an−1+an−2a_n = a_{n-1} + a_{n-2}an=an−1+an−2
an=n⋅an−1a_n = n \cdot a_{n-1}an=n⋅an−1