\begin{definition}[Definition:Limit of Sequence/Rational Numbers]
Let $\sequence {x_n}$ be a sequence in $\Q$.
Let $\sequence {x_n}$ converge to a value $l \in \R$, where $\R$ denotes the set of real numbers.
Then $l$ is a '''limit of $\sequence {x_n}$ as $n$ tends to infinity'''.
This is usually written:
:$\ds l = \lim_{n \mathop \to \infty} x_n$
\end{definition}