\[Y_{n}\left(z\right)=-\frac{(\tfrac{1}{2}z)^{-n}}{\pi}\sum_{k=0}^{n-1}\frac{(n-%
k-1)!}{k!}\left(\tfrac{1}{4}z^{2}\right)^{k}+\frac{2}{\pi}\ln\left(\tfrac{1}{2%
}z\right)J_{n}\left(z\right)-\frac{(\tfrac{1}{2}z)^{n}}{\pi}\sum_{k=0}^{\infty%
}(\psi\left(k+1\right)+\psi\left(n+k+1\right))\frac{(-\tfrac{1}{4}z^{2})^{k}}{%
k!(n+k)!},\]