Consider a sequence of disjoint nonempty intervals $[\ell_{n}, r_{n}) \subseteq [0, 1)$, $n \in \mathbb{N}$, such that $$\sum_{n = 1}^{\infty} (r_{n} - \ell_{n}) = 1,\qquad 0 < r_{n + 1} - \ell_{n + 1} \leq r_{n} - \ell_{n} < 1. $$ My question is, need the set $$A=[0, 1) \setminus \bigcup_{n \in \mathbb{N}} [\ell_{n}, r_{n})$$ be countable? All constructions I've been able to come up with are such that $A$ is countable. Obviously, $A$ has Lebesgue measure $0$, but that does not imply that $A$ is countable.
2026-04-07 14:57:48.1775573868
A Partition of $[0, 1)$
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HINT: No, because it may be obtained as a small modification of the Cantor set construction.