Maps of Many Colors
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|Ivars Peterson (MathLand)|
|The 4-color map theorem: are four colors always enough to fill in every conceivable map that can be drawn on a flat piece of paper so that no countries sharing a common boundary are the same color? A single shared point doesn't count as a shared border. Otherwise, a map whose countries are arranged like the wedges of a pie would need as many colors as there are countries. Also, countries must be connected regions; they can't have colonies scattered all over the map. The four-color problem has intrigued and stumped professional and amateur mathematicians alike ever since it was first proposed in 1852 by a British graduate student, Francis Guthrie, in a letter to his younger brother. In 1976, Kenneth Appel and Wolfgang Haken of the University of Illinois announced that they had finally proved the four-color theorem...|
|Levels:||High School (9-12), College|
|Resource Types:||Problems/Puzzles, Articles|
|Math Topics:||Graph Theory|
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