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Four-Color Map Theorem

Four-Color Map Theorem, a selection of answers from the Dr. Math archives.

Four-Color Map Theorem

I hear the Four-color map theorem was either proved or disproved and that extensive computer effort was required....

Four-Color Theorem

If you wish to color in each "country" or "space" on a map in such a way that no two contiguous countries or spaces have the same color, what is the minimum number of colors you can use?

Four-Color Map Problem

Other than trial and error is there any scientific or mathematical way to solve the Four Color Problem? How about even explaining it in layman's terms?

The Four-Color Map problem

What is the four-color map problem?

What is the Four-Color Theorem?

What is the Four Color Theorem?

Four-Color Theorem - sci-math faq

Do we need more than four colors to color a two-dimensional map?

Four-Color Map Problem: Some History

Could you please give me the history of this topic?

The N-Color Theorem?

What happens if we try to generalize the Four Color Theorem to other numbers of dimensions?

Multi-Dimensional Four-color Theorem

Has any work been done on theorems like the four-color theorem for different dimensions?

Proofs of the Two-Color Map Theorem

Suppose a map is drawn using only lines that extend to infinity in both directions; are two colors sufficient to color the countries so that no pair of countries with a common border have the same color?

Why Not Five Colors, All Touching?

A five-color map problem.

Mobius Strips and the Six-Color Map Theorem

An extension of the four-color map theorem to the mobius strip, i.e. the six-color map theorem.