Editing Perfect number (section)

== External links ==
* {{springer|title=Perfect number|id=p/p072090}}
* David Moews: [http://djm.cc/amicable.html Perfect, amicable and sociable numbers]
* [https://mathshistory.st-andrews.ac.uk/HistTopics/Perfect_numbers/ Perfect numbers – History and Theory]
* {{Mathworld|urlname=PerfectNumber|title=Perfect Number}}
* {{OEIS el|sequencenumber=A000396|name=Perfect numbers|formalname=Perfect numbers n: n is equal to the sum of the proper divisors of n}}
* [https://web.archive.org/web/20181106015226/http://oddperfect.org/ OddPerfect.org] A projected distributed computing project to search for odd perfect numbers.
* [https://www.mersenne.org/ Great Internet Mersenne Prime Search] (GIMPS)
* [http://mathforum.org/dr.math/faq/faq.perfect.html Perfect Numbers], math forum at Drexel.
* {{cite web|last=Grimes|first=James|title=8128: Perfect Numbers|url=http://www.numberphile.com/videos/8128.html|work=Numberphile|publisher=[[Brady Haran]]|access-date=2013-04-02|archive-url=https://web.archive.org/web/20130531000409/http://numberphile.com/videos/8128.html|archive-date=2013-05-31|url-status=dead}}

{{Divisor classes}}
{{Classes of natural numbers}}
{{Authority control}}

{{DEFAULTSORT:Perfect Number}}
[[Category:Divisor function]]
[[Category:Integer sequences]]
[[Category:Unsolved problems in number theory]]
[[Category:Mersenne primes]]
[[Category:Perfect numbers| ]]