. C O ] 3 D ec 1 99 8 A CLASSIFICATION OF CENTRALLY - SYMMETRIC AND CYCLIC 12 - VERTEX TRIANGULATIONS
نویسندگان
چکیده
In this paper our main result states that there exist exactly three combinatorially distinct centrally-symmetric 12-vertex-triangulations of the product of two 2-spheres with a cyclic symmetry. We also compute the automorphism groups of the triangulations. These instances suggest that there is a triangulation of S × S with 11 vertices – the minimum number of vertices required.
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