斯奎斯数

数论中，斯奎斯数（Skewes' number）是指某些极大的数，以南非数学家斯坦利·斯奎斯（Stanley Skewes）的名字命名。他以此来表示满足

$\pi(x) > \operatorname{li}(x)$

的最小自然数x的上界。式中，π表示素数计数函数，li则表示对数积分。经过数学家对这一上界的不断改进，目前发现在$e^{727.95133}$附近有满足上式的自然数，不过仍不清楚这是否是最小的斯奎斯数。

参见

• 素数定理

参考文献

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