\[\mathsf{P}^{-\mu}_{\nu}\left(x\right)=\frac{\left(1-x^{2}\right)^{-\mu/2}}{%
\Gamma\left(\mu\right)}\int_{x}^{1}\mathsf{P}_{\nu}\left(t\right)(t-x)^{\mu-1}%
\,\mathrm{d}t,\]