Lebesgue's density theorem
In mathematics, Lebesgue's density theorem states that for any Lebesgue measurable set A ⊆ R n {\displaystyle A\subseteq \mathbb {R} ^{n}} , the "density" of A {\displaystyle A} is 0 or 1 at almost every point in R n {\displaystyle \mathbb {R} ^{n}} . Additionally, the "density" of A {\displaystyle A} is 1 at almost every point of A {\displaystyle A} .
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