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Odd Perfect Numbers Have At Least Nine Distinct Prime Factors

Pace P. Nielsen
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Abstract

An odd perfect number, N, is shown to have at least nine distinct prime factors. If 3 does not divide N, then N must have at least twelve distinct prime divisors. The proof ultimately avoids previous computational results for odd perfect numbers.

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Pace P. Nielsen. 2006-02-22. Odd Perfect Numbers Have At Least Nine Distinct Prime Factors. https://doi.org/10.1090/s0025-5718-07-01990-4

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