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# Tag Archives: coloring maps

## Four color theorem: experimenting impasses (as in life)

I still think a solution may be found in Kempe chain color swapping … for maps without F2, F3 and F4 faces (or even without this restriction). Or at least I want to try. How you can solve the impasses … Continue reading

Posted in math
Tagged 3-edge coloring, 4ct, coloring maps, four color problem, Kempe chain, Tait coloring
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## Four color theorem: work in progress

😦 Too many more things to do and little time: Filter out duplicates. I finally found a java library to efficiently filter out all isomorphic graphs. It is a library part if the sspace project. Using it I will be able … Continue reading

Posted in math
Tagged 4ct, Cahit spiral chains, coloring maps, four color theorem, Graph theory, tait, Tait coloring
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## Four color theorem: Cahit spiral chains (step two)

Now the application is able to find all spiral chains of a graph. I still need to: Implement the Cahit coloring algorithm using the spiral chains Add some additional features to the Java application Modify the settings to color the … Continue reading

Posted in Uncategorized
Tagged 4ct, Cahit spiral chains, coloring maps, Four color, Tait coloring
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## Four color theorem: videos

Four videos for the four color theorem. music coloring algorithm slow motion maps java application features

Posted in math
Tagged coloring maps, four color problem, four color theorem, graph coloring, pencil and paper
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## Four color theorem: other representations of maps

Here are some new representation of graphs: Thanks to: http://mathoverflow.net/questions/63861/representations-of-regular-maps-four-color-theorem http://www.geogebra.org/forum/viewtopic.php?f=2&t=21841

## Four color theorem: representations of maps

For the scope of the four color problem and without lack of generality, maps can be represented in different ways. This is generally done to have a different perspective on the problem. For example, the graph-theoretic representation of maps has … Continue reading

## Counting maps

I’ve posted this question on mathoverflow. Is there a formula to count how many different topological regular maps can be created with n faces (on a sphere)? For “regular” I intend maps in which the boundaries form a 3-regular planar … Continue reading