# Definition:Generating Function/Parameter

## Definition

Let $G_A \left({z}\right)$ be a generating function for the sequence $A$.

The variable $z$ is a dummy variable, known as the parameter of $G_A \left({z}\right)$.

## Also denoted as

The symbol used for the parameter varies.

$x$ is often used instead.

In the field of probability theory $s$ tends to be the symbol of choice.

Some authors use $\zeta$.