The Pappus configuration is the 
configuration illustrated
above that appears in Pappus's hexagon theorem.
It is one of the three 
configurations.
The Levi graph of the Pappus configuration is known as the Pappus graph.
See also
Pappus Graph, Pappus's Hexagon Theorem
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References
Berman, L. W.; Gévay, G.; and Pisanski, T. "Polycyclic Geometric Realizations of the Gray Configuration." 20 Feb 2025. https://arxiv.org/abs/2502.14484.Coxeter, H. S. M. "Self-Dual Configurations and Regular Graphs." Bull. Amer. Math. Soc. 56, 413-455, 1950.Grünbaum, B. Configurations of Points and Lines. Providence, RI: Amer. Math. Soc., pp. 1-2 and 9, 2009.
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Cite this as:
Weisstein, Eric W. "Pappus Configuration." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/PappusConfiguration.html