17 citations · 17 across the 1 of their papers we have counts for
2 papers
math.NT2006★ 17 cited
Odd Perfect Numbers Have At Least Nine Distinct Prime Factors
Pace P. Nielsen
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 ultimat…
math.RA2004
Countable and Full Exchange Rings
Pace P. Nielsen
We show that a suitable ring with a ``nice'' topology, in which convergent limits of units are units, is an \aleph_0-exchange ring. We generalize the argument to show that a semi-r…