Wolfram Function Repository
Instantuse addon functions for the Wolfram Language
Function Repository Resource:
Compute the vertex chromatic number of a graph
ResourceFunction["ChromaticNumber"][g] computes χ(g) the vertex chromatic number of simple graph g. 
Compute chromatic numbers of simple graphs:
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Compute chromatic numbers of graphs:
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Compute the vertex chromatic number of famous graphs:
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Works on graphs in either 2D or 3D form:
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Special and corner cases are handled efficiently:
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Compute on larger graphs than was possible before (with Combinatorica`):
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ChromaticNumber does not work on the output of GraphPlot:
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