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Category Archives: Polyhedra
Cube complexes, Reidemeister 3, zonohedra and the missing 8th region
There is an old puzzle which starts by asking: what is the next number in the sequence 1,2,4,? We are supposed to recognize the start of the sequence and answer that the next number is surely 8, because the first … Continue reading
Zonohedra and the SylvesterGallai theorem
When I was in Melbourne recently, I spent some time browsing through a copy of “Twelve Geometric Essays” by Harold Coxeter in the (small) library at AMSI. One of these essays was entitled “The classification of zonohedra by means of … Continue reading
Posted in Polyhedra, Projective geometry
Tagged Coxeter, projective plane, SylvesterGallai theorem, zonohedra
4 Comments