Octahedron Nieuwland number
Prove that the Octahedron has Nieuwland number equal to 3√2/4, thereby establishing the conjectured optimal passage ratio for this Platonic solid.
References
It is, for instance, still open to prove that the Octahedron has Nieuwland number 3√2/4
— A convex polyhedron without Rupert's property
(Steininger et al., 25 Aug 2025) in Section 9.2, Open Problems