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Summary
DescriptionCayley graphs of the quaternion group.png
English: Two isomorphic Cayley graphs of the quaternion group. The diagram on the left shows the graph traced in the plane. Edge crossing cannot be avoided using the plane. To avoid edge crossing, we must move to a surface of higher genus, in this case the torus. The toroidal embedding is shown in the diagram on the right. In representing the torus as a rectangle, opposite edges should be identified. Tools used: wikipedia:Inkscape.
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