N ov 2 00 6 ENUMERATIVE PROPERTIES OF TRIANGULATIONS OF SPHERICAL BUNDLES OVER S 1
نویسندگان
چکیده
We give a complete characterization of all possible pairs (f 0 , f 1), where f 0 is the number of vertices and f 1 is the number of edges, of any sim-plicial triangulation of an S k-bundle over S 1. The main point is that Kühnel's triangulations of S 2k+1 × S 1 and the nonorientable S 2k-bundle over S 1 are unique among all triangulations of (n − 1)-dimensional homology manifolds with first Betti number nonzero, vanishing second Betti number and 2n + 1 vertices.
منابع مشابه
Enumerative Properties of Triangulations of Spherical Bundles over S
We give a complete characterization of all possible pairs (f0, f1), where f0 is the number of vertices and f1 is the number of edges, of any simplicial triangulation of an Sk-bundle over S1. The main point is that Kühnel’s triangulations of S2k+1 × S1 and the nonorientable S2k-bundle over S1 are unique among all triangulations of (n − 1)-dimensional homology manifolds with first Betti number no...
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