Is $$\sum_{n=1}^\infty \frac{1}{\text{lcm}[1,~2,~\ldots,~n]} $$ an irrational number? I just thought up of the problem, and can anyone help this out?
2026-03-28 21:51:42.1774734702
Is $\sum_{n=1}^{\infty} \frac{1}{\operatorname{lcm}[1,~2,~\ldots,~n]}$ irrational?
133 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in SEQUENCES-AND-SERIES
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