nLab partial sum

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.

Related concepts

• series

• Taylor series

References

See also:

• Wikipedia, Partial sum