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Erdős problem 442

Let Log⁡x:=max⁡{log⁡x,1}\operatorname{Log} x := \max\{\log x, 1\}, Log⁡2x=Log⁡(Log⁡x)\operatorname{Log}_2x = \operatorname{Log} (\operatorname{Log} x), and Log⁡3x=Log⁡(Log⁡(Log⁡x)).\operatorname{Log}_3x = \operatorname{Log}(\operatorname{Log}(\operatorname{Log} x)). Is it true that if A⊆NA\subseteq\mathbb{N} is such that 1Log⁡2x∑n∈A:n≤x1n→∞ \frac{1}{\operatorname{Log}_2 x} \sum_{n\in A: n\leq x} \frac{1}{n}\to\infty then (∑n∈A:n≤x1n)2∑n,m∈A:n<m≤x1lcm⁡(n,m)→∞ \left(\sum_{n\in A: n\leq x} \frac{1}{n}\right)^2 \sum_{n, m \in A: n < m \leq x} \frac{1}{\operatorname{lcm}(n, m)}\to\infty as x→∞x\to\infty?

Erdős Problems records this as disproved.

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How far the record reaches4 of 6 stages
  1. Sourceerdos-problems
  2. StatementRetained
  3. Formal2 retained
  4. Resolutiondisproved
  5. WorkNone recorded
  6. DecisionNone here
  7. The questionNot reached
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Where the source files it575 share a topic
Erdős problem 321accepted
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