Definition:Accumulation Point/Set

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Definition

Let $\paren { S, \tau }$ be a topological space.

Let $A \subseteq S$.

Let $x \in S$.


Then $x$ is an accumulation point of $A$ if and only if:

$x \in \cl {A \setminus \set x}$

where $\operatorname{cl}$ denotes the (topological) closure of a set.


Also see

  • Results about accumulation points can be found here.


Sources