Density of Carmichael numbers with three prime factors
نویسندگان
چکیده
We get an upper bound ofO(x5/14+o(1)) on the number of Carmichael numbers ≤ x with exactly three prime factors.
منابع مشابه
Density of Carmichael Numbers with Three Prime Factors 1707
We get an upper bound of O(x 5=14+o(1)) on the numberof Carmichael numbers x with exactly three prime factors.
متن کاملCarmichael Numbers With Three Prime Factors
A Carmichael number (or absolute pseudo-prime) is a composite positive integer n such that n|an − a for every integer a. It is not difficult to prove that such an integer must be square-free, with at least 3 prime factors. Moreover if the numbers p = 6m + 1, q = 12m + 1 and r = 18m + 1 are all prime, then n = pqr will be a Carmichael number. However it is not currently known whether there are i...
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ورودعنوان ژورنال:
- Math. Comput.
دوره 66 شماره
صفحات -
تاریخ انتشار 1997