Contents

# Contents

## Definition

In analysis, given a series

$\underoverset {k = 0} {\color{blue}\infty} {\sum} a_k$

its $n$th partial sum (for $n \in \mathbb{N}$ any natural number) is the actual sum

$\underoverset {k = 0} {\color{blue}n} {\sum} a_k$

of the first $n+1$ summands.