Numbers whose positive divisors have small integral harmonic mean
نویسنده
چکیده
A natural number n is said to be harmonic when the harmonic mean H(n) of its positive divisors is an integer. These were first introduced almost fifty years ago. In this paper, all harmonic numbers less than 2 × 109 are listed, along with some other useful tables, and all harmonic numbers n with H(n) ≤ 13 are determined.
منابع مشابه
All numbers whose positive divisors have integral harmonic mean up to 300
A positive integer n is said to be harmonic when the harmonic mean H(n) of its positive divisors is an integer. Ore proved that every perfect number is harmonic. No nontrivial odd harmonic numbers are known. In this article, the list of all harmonic numbers n with H(n) ≤ 300 is given. In particular, such harmonic numbers are all even except 1.
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عنوان ژورنال:
- Math. Comput.
دوره 66 شماره
صفحات -
تاریخ انتشار 1997