John Conway passed away a few days ago. He was a favorite among mathematical educators and communicators. He was involved in a large array of interesting projects and results during his career, many that can easily fascinate even the most disinterested people when it comes to mathematics.
Here are a few things he worked on, listed roughly in the order in which I came across them in my mathematical life.
- Look-and-Say Sequence
- Game of Life
- Doomsday Algorithm
- Sporadic Groups (and far more generally, the classification of the finite simple groups)
- Surreal Numbers
Any of these are a treat to look into. Conway was a powerhouse of interesting and engaging ideas. Take a look at the Numberphile videos involving him for a slice of the world from his perspective.