I am not sure how to prove there is no Lebesgue number for an open cover {(1/n,1)} of interval (0,1). If I take any element x of (0,1), it is inside any of the open set Ux = (1/n,1) of the open cover. So I am not sure how taking a ball of radius r around x is not contained in any Ux.(adsbygoogle = window.adsbygoogle || []).push({});

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# How to prove there is no Lebesgue number for open cover (1/n,1)?

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