Graph Theory pp 115-133 | Cite as

To the Moon and Beyond

  • Ellen GethnerEmail author
Part of the Problem Books in Mathematics book series (PBM)


Are there nontrivial integer solutions to the equation xn + yn = zn for any integer n ≥ 2? How about for n > 2? Wait a minute! Is this a chapter about Fermat’s Last Theorem or about Graph Coloring? From one point of view, theorems such as The Four Color Theorem and Fermat’s Last Theorem are no more important than countless other problems in chromatic graph theory or in diophantine equations, respectively, and yet both problems are pervasive in science and culture.



I would like to express my appreciation to Thom Sulanke for our collaboration on the Earth-Moon problem, and for sharing his history and related correspondence, which has added another dimension of enjoyment to the adventure.


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© Springer Nature Switzerland AG 2018

Authors and Affiliations

  1. 1.University of Colorado DenverDenverUSA

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