当指定Z为复数变元时，就有了形式幂级数的“变换”函数，即闭合形式的问题。

When Z is assigned the meaning of a complex variable, problem of "closed form" of formal power series emerges.

youdao

当指定Z为复数变元时，就有了形式幂级数的“变换”函数，即闭合形式的问题。

When Z is assigned the meaning of a complex variable, problem of "closed form" of formal power series emerges.

youdao