\begin{definition}[Definition:Power Series/Coefficient]
Let $\ds \sum_{n \mathop = 0}^\infty a_n \paren {x - \xi}^n$ be a power series.
The terms:
:$a_0, a_1, \ldots, a_n, \ldots$
are the '''coefficients''' of $\ds \sum_{n \mathop = 0}^\infty a_n \paren {x - \xi}^n$.
\end{definition}