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  "body": "\n## Definition\n\nLet $S$ be a subset of $\\mathbb{R}$ and let $a$ be a real number.\nThe point $a$ is a limit point of $S$ if for each $\\delta \u003e 0$ there is $x \\in S$ with $0 \u003c |x - a| \u003c \\delta$.\n\n## Remarks\n\nA limit point of $S$ need not belong to $S$. For example, $0$ is a limit point of $\\{1/n : n \\ge 1\\}$.\nEach point of an interval with more than one point is a limit point of the interval. So are its endpoints.\nLimit points of the domain are the points where the [[limit of a function|0TXTSEMHR5]] makes sense.\nMathlib uses the general form `AccPt`.\n\n## Explanations\n\n### L1 human\n\nA limit point of $S$ is a point that we can approach by other points of $S$.\nPoints of $S$ lie as close to it as we like, not counting the point itself.\n",
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