|SHORT TALKS BY POSTDOCTORAL MEMBERS|
|Topic:||Perfect Numbers and Their Friends|
|Affiliation:||Member, School of Mathematics|
|Date:||Wednesday, September 30|
|Time/Room:||4:00pm - 5:00pm/S-101|
Let s(n) denote the sum of the proper divisors of the natural number n. We call n *perfect* if n = s(n) and *amicable* if n = s(s(n) . We discuss some old problems and recent results related to perfect numbers, amicable numbers, and their generalizations.