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A perfect number is a positive integer that is equal to the sum of its proper positive divisors.
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What is the latest progress in the research on Odd Perfect numbers?
I am not claiming that I do know the latest update about perfect numbers. However, I believe that still nobody has proved that there are no odd perfect numbers (despite of some doubtful papers on the …
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Integers n such that sigma(n)=omega(n)n and omega(n) divides n
For $n=120$ we have $\omega(120)=3$ and $\sigma(120)=360=3\cdot 120=\omega(120)\cdot 120$
with $\omega(120)\mid 120$. This is not an even perfect number.