\[\tfrac{1}{2}\left(x^{2}-1\right)^{1/2}\frac{P^{\mu}_{\nu}\left(x\right)}{P^{%
\mu-1}_{\nu}\left(x\right)}=\cfrac{x_{0}}{y_{0}+\cfrac{x_{1}}{y_{1}+\cfrac{x_{%
2}}{y_{2}+\cdots}}},\]