I am trying to solve for the values of a variable $u_t$. $u_t$ is defined as:
$(1-L-L^2)u_t = \epsilon_t$
where $L$ is the lag operator and $t=1,...,n$. $\epsilon_t$ is a random variable (normal[0,1]) that can be generated. Using the values of $\epsilon_t$, how can I solve for $u_t$.