0}\end{gathered}$$ and $$\begin{gathered} {  \begingroup   \begingroup\lccode`~=`,     \lowercase{\endgroup\def~}{\pFcomma\mkern\pFqskip}  \mathcode`,=\string"0000   {}_{}F_{0}\biggl(\genfrac..{0pt}{}{0a; a+0/0,0a-0}{0a+0/0};\frac{0}{00}, \frac{0}{0}\biggr)  \endgroup }