{} sub p F sub q left ( a sub 1 , ... , a sub p ; c sub 1 , ... , c sub q ; z right ) = sum from {n = 0} to inf {{left ( a sub 1 right )} sub n \[u22EF] {left ( a sub p right )} sub n} over {{left ( c sub 1 right )} sub n \[u22EF] {left ( c sub q right )} sub n} {z sup n} over {n !}