Definition:Limit Point/Metric Space/Definition 2

Definition
Let $M = \struct {S, d}$ be a metric space.

Let $\tau$ be the topology induced by the metric $d$.

Let $A \subseteq S$ be a subset of $S$.

Let $\alpha \in S$.

Then $\alpha$ is a limit point of $A$ there is a sequence $\sequence{\alpha_n}$ in $A$ such that $\alpha$ is a limit point of the sequence $\sequence{\alpha_n}$, considered as sequence in $S$.