Erdős Problem #1201
Nothing has been published against this problem here, and nobody has checked anything. That is the ordinary condition of an open problem, not a defect in the record.
Statement
Is it true that for every there exists a such that the density of for which is at least , where is the greatest prime divisor of ? A short argument via the Matomäki-Radziwiłł theorem establishes the lower-density version.
Context
As Tao notes on the problem page, the claim establishes natural LOWER density at least 1-eta but not that the natural density exists, so the problem as stated remains technically open
A numbered problem from the Erdos catalog: real and documented, with a specialist audience. Checked against erdosproblems.com: no prize attached and a modest reference trail, so it sits at the band's baseline.
People
Projects
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Interest
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Attempts
No person has examined this. 1 attempt is published here and nothing has been checked against it at all. Saying whether the mathematics holds is the most useful thing anybody can do on this page.
The deduction from the Matomäki-Radziwiłł theorem on multiplicative functions was written by GPT-5.5 Pro; Tao and Sawin's forum discussion pinned down exactly what the known results do and do not give for this problem.
As Tao notes on the problem page, the claim establishes natural LOWER density at least 1-eta but not that the natural density exists, so the problem as stated remains technically open
Reviews
0 human reviews · 0 machine checksNo person has reviewed this attempt. It has not been checked at all.
Endorsements
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Discussion of this attempt
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Discussion
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