Notebook Archive
Empire Problem
Eric W. Weisstein
Author
Eric W. Weisstein
Title
Empire Problem
Description
The empire problem, also known as the m-pire problem) asks for the maximum number of colors needed to color countries such that no two countries sharing a common border have the same color (this is the usual four-color theorem) in the case where each country consists of m disjoint regions. Heawood (1890) showed that 6m colors are sufficient, and for the case m=2, 12 colors are also necessary (Gardner 1997; Frederickson 2002, pp. 31-32).
Category
Educational Materials
Keywords
URL
http://www.notebookarchive.org/2019-07-0z3vtr2/
DOI
https://notebookarchive.org/2019-07-0z3vtr2
Date Added
Date Last Modified
2019-07-02
File Size
0.83 megabytes
Supplements
Rights
Redistribution rights reserved
Cite this as: Eric W. Weisstein, "Empire Problem" from the Notebook Archive (2018), https://notebookarchive.org/2019-07-0z3vtr2
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