Answering a question on quora.com: Can I do math as a hobby?
Yes, by all means! While you may think that doing math means boring computations, nothing could be farther from the truth. There is a whole field called recreational mathematics—no, that is not an oxymoron. True, higher mathematics usually requires years of study just to be able to understand the questions. That is not the case in recreational mathematics.
Recreational mathematics are puzzles and games, pure and simple. They are fun and entertaining, but there are mathematical ideas, sometimes quite deep ones, behind them. The key criteria is approachability. Recreational mathematics problems are accessible. Like with any game, there are a few usually simple rules. Within the context of the rules there is a rich number of relationships and discoveries to be found. A lot of good puzzles are geometrical in nature: tangrams, origami, soma cubes, a Rubic’s cube—the list is long. There are logic puzzles, codes and cyphers, and cellular automata such as Conway’s Game of Life.
A good place to start is with the writer Martin Gardner. Gardner wrote a monthly column on recreational mathematics for Scientific American for a number of years. His columns were collected in a number of books.
Yes, computations are boring, but they are just the tiniest piece of the fascinating field of mathematics. As a retired mathematics professor, I am naturally biased. However, it you take the time to look into it, I think you will find something fascinating to play with. Yes, recreation!