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It fits the formulation of the OP Q better.
Wlod AA
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It is not possible, and even quite a bit more is not possible.

Let $\ f(m)\ $ be the number of the $m$-th partition intervals which intersect $\ A.\ $

Theorem  There exists $\ A\ $ which is not dense in any non-trivial interval whenever

$$ \lim_{m=\infty} \frac {f(m)}m\ =\ 0 $$

Proof  The required $\ A\ $ can be given as follows:

$$ A\ :=\\ \ \left\{ \frac {2\cdot k-1}{2\cdot m}: \ m\in\Bbb N\ \ \text{and} \ \ k\in\Bbb Z\ \ \text{and}\ \ 0<k\le f(m)\,\right\} $$

End of Proof

Wlod AA
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