五千年(敝帚自珍)

主题:【原创】今天的数学(系列) -- qiaozi

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家园 高斯的估计可以无穷多次地取到精确值,这是有定理保证的。

我们现在似乎还不能断言对于某个特定的x,高斯的估计是不是可以精确到让人咂舌的地步

http://mathworld.wolfram.com/PrimeNumberTheorem.html

For small n, it had been checked and always found that π(n)<Li(n). As a result, many prominent mathematicians, including no less than both Gauss and Riemann, conjectured that the inequality was strict. To everyone's surprise, this conjecture was refuted when Littlewood (1914) proved that the inequality reverses infinitely often for sufficiently large n (Ball and Coxeter 1987; Havil 2003, p. 199). Skewes then showed that the first crossing of π(n)-Li(n) occurs before 10^(10^(10^34)),

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