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# Tag Archives: graph coloring

## Four color theorem: about edges selection

For the decomposition of a graph representing a map, I’m trying to use different algorithms to select the edge to remove. The question is: When you have multiple valid choices, which is the best edge to select … if any? Some basic … Continue reading

## Four color theorem: almost there?

Here there are some results that came out from the study of Kempe chains/cycles (of edges) in Tait coloring of a 3-regular planar graph. Next is shown an image with a summary of the ideas behind this approach. I didn’t have the time to … Continue reading

Posted in math
Tagged Alfred Bray Kempe, four color theorem, graph coloring, Tait coloring
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## Four color theorem: Cahit spiral chains

Hi, I’ve found some time to implement the first version of Cahit Spiral Chains algorithm. I still need to: Find all spiral chains of a given graph and not only one (changing the starting point) I need to implement the … Continue reading

Posted in Uncategorized
Tagged 4ct, Cahit spiral chains, four color theorem, graph coloring, Graph theory, 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