Red Net
The coloring red of two complete subgraphs of n/2 points (for even n) in order to generate a blue-empty graph.
See also
Blue-Empty Graph, Complete GraphExplore with Wolfram|Alpha
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Cite this as:
Weisstein, Eric W. "Red Net." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/RedNet.html