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\homework{6: The Four-Color Theorem}{Due Friday, Week 4}

This is too much fun to not assign it as the only problem.

\begin{enumerate}
\item Find the flaw in the proof of the four-color theorem we gave in class!  That is: explain why the proof we made in class is mistaken, or omits a key case that we would need to consider.
\end{enumerate}



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