arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2006.16491math.NT
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关于半素数的计数函数

On the counting function of semiprimes

Dragos Crisan, Radek Erban

摘要:

一个半素数是一个自然数,可以写成两个素数的乘积。研究了半素数个数小于等于$x$的函数$π_2(x)$的渐近性质.使用组合的论点,渐近级数的$π_2(x)$确定,所有的条款明确给出。本文提出了一种计算渐近级数中常数的算法,并将常数计算到20位有效数字。研究了渐近级数部分和的误差。这种方法的推广$k$素数的产品,$k\geq 3$,也提出了。

英文摘要:

A semiprime is a natural number which can be written as the product of two primes. The asymptotic behaviour of the function $π_2(x)$, the number of semiprimes less than or equal to $x$, is studied. Using a combinatorial argument, asymptotic series of $π_2(x)$ is determined, with all the terms explicitly given. An algorithm for the calculation of the constants involved in the asymptotic series is presented and the constants are computed to 20 significant digits. The errors of the partial sums of the asymptotic series are investigated. A generalization of this approach to products of $k$ primes, for $k\geq 3$, is also proposed.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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