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# Category Archives: Uncategorized

## 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: 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: deep analysis of a map

I would like to implement a brute force algorithm to search ALL the different colorings of a map. Here is the question on: math.stackexchange.com In terms of graph theory I’d like to find all four colorings of the vertices of … Continue reading

Posted in Uncategorized
Tagged 4, algorithm, color, colour, different, four, proper colorings, theorem
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## Four color theorem: java application update

I new version of the java application is available with these new features: Save .png images and restore maps from the image itself (using metadata within it) Force coloring of faces to find different colorings of the same map Faster … Continue reading

Posted in Uncategorized
Tagged 4, color, colour, four, four color theorem, Java, new features, theorem
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## Four color theorem: hello world

These translations have been taken from wikipedia, starting from http://en.wikipedia.org/wiki/Four_color_theorem. I was just curious to see if people search for the “four color theorem” only in english. Teorema dei quattro colori Problém čtyř barev Firfarveproblemet Vier-Farben-Satz قضیه چهاررنگ Théorème des … Continue reading

## 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