Brain-teasers and mathematical puzzles.

Note: the boundary between these idle puzzles and real mathematics is not especially clear! Not only is there a good deal of "real" mathematics illustrated in many games (e.g. most of the ones featured at this site) but there is even a branch of mathematics called "combinatorial game theory" which dresses up some of these games in academic garb!

Sums & Products -- classic Martin Gardner puzzle about determining a pair of numbers from information about their sum and product.

TUNESOAP -- collect sets of cards with letters T,U,... on them

See also this site with a collection of puzzles: classic puzzles and brain teasers

• My home page is just a short introduction to the pages I maintain
• The parent page to this one is dedicated to other mathematical games and mathematical analyses of "regular" games.
• I keep a large set of pages which provide a thematic introduction to the subject areas of modern mathematics, complete with answers to thousands of more or less common questions.

This page is

	http://www.math.niu.edu/~rusin/uses-math/games/teasers/index.html