Jaydeep Chipalkatti, Pascal's hexagram and the geometry of the Ricochet configuration,
Forum Geometricorum, 17 (2017) 73--91.

Abstract. This paper is a study of a geometric arrangement called the `ricochet configuration' (or R-configuration), which arises in the context of Pascal's theorem. We give a synthetic proof of the fact that a specific pair of Pascal lines is coincident for a sextuple in R-configuration. Furthermore we calculate the symmetry group of a generic R-configuration, and consequently the degree of the subvariety Rico is a subset of P^6 of all such configurations. We also find a set of equivariant defining equations for Rico, and show that it is an intersection of two invariant hypersurfaces.

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