The ALMOST Perfect Numbers

This is my entry in #SoMEpi . The perfect numbers are some of the most famous in all of number theory. But since perfection is so hard to achieve, we're naturally drawn to the mathematical quest for perfection. That manifests itself in the form of many types of almost perfect numbers. 70 is weird: youtube.com/watch?v=jrhVJKSKNwk 0:00 Intro 2:04 Descartes 6:06 Quasi perfect 8:11 Almost perfect 9:44 Aliquot sequences 15:37 Multiply perfect 19:00 Hemi perfect 20:06 Relative abundance clubs 22:51 Near perfect 24:43 Unitary perfect 26:46 Sublime 28:55 Outro #math #numbertheory #perfectnumber