Abstract
Any 7-colorable 1-knot has a 7-colored diagram such that exactly four colors of seven are assigned to the arcs of the diagram.
Citation
Kanako OSHIRO. "Any 7-colorable knot can be colored by four colors." J. Math. Soc. Japan 62 (3) 963 - 973, July, 2010. https://doi.org/10.2969/jmsj/06230963
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