The third largest prime divisor of an odd perfect number exceeds one hundred
نویسنده
چکیده
Let σ(n) denote the sum of positive divisors of the natural number n. Such a number is said to be perfect if σ(n) = 2n. It is well known that a number is even and perfect if and only if it has the form 2p−1(2p − 1) where 2p − 1 is prime. It is unknown whether or not odd perfect numbers exist, although many conditions necessary for their existence have been found. For example, Cohen and Hagis have shown that the largest prime divisor of an odd perfect number must exceed 106, and Iannucci showed that the second largest must exceed 104. In this paper, we prove that the third largest prime divisor of an odd perfect number must exceed 100.
منابع مشابه
The second largest prime divisor of an odd perfect number exceeds ten thousand
Let σ(n) denote the sum of positive divisors of the natural number n. Such a number is said to be perfect if σ(n) = 2n. It is well known that a number is even and perfect if and only if it has the form 2p−1(2p − 1) where 2p − 1 is prime. No odd perfect numbers are known, nor has any proof of their nonexistence ever been given. In the meantime, much work has been done in establishing conditions ...
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ورودعنوان ژورنال:
- Math. Comput.
دوره 69 شماره
صفحات -
تاریخ انتشار 2000