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All Random Solved Random Open
OPEN
Is it true that there are only finitely many pairs of intervals $I_1,I_2$ such that \[\sum_{n_1\in I_1}\frac{1}{n_1}+\sum_{n_2\in I_2}\frac{1}{n_2}\in \mathbb{N}?\]
This is still open even if $\lvert I_2\rvert=1$. It is perhaps true with two intervals replaced by any $k$ intervals.