# The Hypergeometric Series

For more information on the Hypergeometric Series, see [[Husemöller, 1987](../../references.md#cite-husem87)], page 176.

## `HypergeometricSeries(a, b, c, z): RngElt, RngElt, RngElt, RngElt -> RngElt`

Return the hypergeometric series $F(a,b,c;z)$ defined by

$$
F(a,b,c;z) = \sum_{0\le n} {{(a)_n(b)_n}\over{n!(c)_n} z^n}
$$

where $(a)_n = a (a+1) \cdots (a+n-1)$.