$H(z)=1+2z^{-1}+z^{-2}$
We know the formula
$a_{m-1}\;(k)=\frac{a_m\;(k)-k_m\;a_m\;(m-k)}{1-k_m\;^2}$
Here $k_2=1$ That makes $a_{m-1}\;(k)=infinity$
How to find lattice coefficients of all pole IIR filter with filter coefficient $k_m$ is 1?
I have read this answer but it is not similar to this question