Definition of limit points of a sequence

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$(a)$Suppose that $\{x^{(n)}\}^{(\infty)}_{(n=m)}$ is a sequence of points in a metric space $(X,d)$, and let $L \in X$. We say that $L$ is a limit point of $\{x^{(n)}\}^{(\infty)}_{(n=m)}$ iff for every $N \ge m$ and $\epsilon \gt 0$ there exists an $n \ge N$ such that $d(x^{(n)}, L) \le \epsilon$.

$(b)$Suppose that $\{x^{(n)}\}^{(\infty)}_{(n=m)}$ is a sequence of points in a metric space $(X,d)$, and let $L \in X$. We say that $L$ is a limit point of $\{x^{(n)}\}^{(\infty)}_{(n=m)}$ iff for every $\epsilon \gt 0$ there exists an $n$ such that $d(x^{(n)}, L) \le \epsilon$. ?


Is $(a)$ equivalent to $(b)$? Obviously $(a) \Rightarrow (b)$, and for the converse let $N \in \mathbb Z$ and let $d_0 = min\{d(x^{(i)}, L), i \lt N\}$, then there exist $m$ such that $d(x^{(m)}, L) \lt d_0/2$.

Is this reasoning correct? (feel free to edit the format or to ask for clarifications and thank you for your time)

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Suppose there is an n where x(n)=L. This would make L a limit point by (b), but not by (a)

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(b) is not correct, we need infinitely many points of the sequence as close to $L$ as we like , not just one or even finitely many (otherwise $x^{(1)} = L$ would be enough to make $L$ a "(b)-limit point", e.g.) and this can only be ensured by asking for indices beyond any finite $N$. What sequences do "at infinity" (for larger and larger indices) is what matters, not incidental stuff like some finitely many values or some such.