What is a free double category like?
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Robert Dawson; Robert Paré
📂
Article
📅
2002
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Elsevier Science
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English
⚖ 151 KB
We give a geometric description of the free double category generated by a double re exive graph. Its cells are homotopy classes of colourings of certain rectangular complexes in the plane. A number of examples illustrate the wide variety of combinatorial properties of the plane this touches.