A puzzle is a problem or enigma that challenges ingenuity. People often contrive such problems as a form of entertainment, but they can also stem from serious mathematical or logistical problems — in such cases, their successful resolution can be a significant contribution to mathematical research.
| Perplexing Problems - http://www.perplexingproblems.fxsonet.com/ The home page for Perplexing Problems. Where people can solve problems set by other users. - [Read more] |