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A new bound for the smallest $x$ with $π(x) > li(x)$

Kuok Fai Chao·Roger Plymen
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Abstract

We reduce the leading term in Lehman's theorem. This improved estimate allows us to refine the main theorem of Bays and Hudson. Entering $2,000,000$ Riemann zeros, we prove that there exists $x$ in the interval $[exp(727.951858), exp(727.952178)]$ for which $π(x)-\li(x) > 3.2 \times 10^{151}$. There are at least $10^{154}$ successive integers $x$ in this interval for which $π(x)>\li(x)$. This interval is strictly a sub-interval of the interval in Bays and Hudson, and is narrower by a factor of about 12.

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Kuok Fai Chao, Roger Plymen. 2009-03-23. A new bound for the smallest $x$ with $π(x) > li(x)$. https://arxiv.org/abs/math/0509312

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