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Bjørn Kjos-Hanssen
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No, let $X$ be the of those irrationals in $x\in (0,1)$ with binary expansion $$x=0.x_1x_2\dots$$ such that if we use a bijection $\mathbb N^2\to\mathbb N$ to represent $x$ as infinitely many reals $x^{(1)}, x^{(2)},\dots$ then $$\lim_{n\to\infty} 1_{\mathbb Q}(x^{(n)})$$ exists.

Here $1_{\mathbb Q}(y)=1$ if $y\in\mathbb Q$ and 0 otherwise.

Bjørn Kjos-Hanssen
  • 24.8k
  • 3
  • 58
  • 114