\[\begin{pmatrix}j_{1}&j_{2}&j_{3}\\
0&0&0\end{pmatrix}=\begin{cases}0,&\mbox{$J$ odd},\\
(-1)^{\frac{1}{2}J}\left(\dfrac{(J-2j_{1})!(J-2j_{2})!(J-2j_{3})!}{(J+1)!}%
\right)^{\frac{1}{2}}\dfrac{\left(\frac{1}{2}J\right)!}{\left(\frac{1}{2}J-j_{%
1}\right)!\left(\frac{1}{2}J-j_{2}\right)!\left(\frac{1}{2}J-j_{3}\right)!},&%
\mbox{$J$ even}.\end{cases}\]