Centrally symmetric graphs
نویسندگان
چکیده
منابع مشابه
Face Numbers of Centrally Symmetric Polytopes Produced from Split Graphs
We analyze a remarkable class of centrally symmetric polytopes, the Hansen polytopes of split graphs. We confirm Kalai’s 3d conjecture for such polytopes (they all have at least 3d nonempty faces) and show that the Hanner polytopes among them (which have exactly 3d nonempty faces) correspond to threshold graphs. Our study produces a new family of Hansen polytopes that have only 3d + 16 nonempty...
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A centrally symmetric 2d-vertex combinatorial triangulation of the product of spheres S × Sd−2−i is constructed for all pairs of non-negative integers i and d with 0 ≤ i ≤ d − 2. For the case of i = d − 2 − i, the existence of such a triangulation was conjectured by Sparla. The constructed complex admits a vertex-transitive action by a group of order 4d. The crux of this construction is a defin...
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Let d ≥ 2 and let K ⊂ R be a convex body containing the origin 0 in its interior. Let, for each direction ω, the (d − 1)–volume of the intersection of K and an arbitrary hyperplane with normal ω attain its maximum if the hyperplane contains 0. Then K is symmetric about 0. The proof uses a linear integro–differential operator on S, whose null–space needs to be, and will be determined.
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ژورنال
عنوان ژورنال: Czechoslovak Mathematical Journal
سال: 1968
ISSN: 0011-4642,1572-9141
DOI: 10.21136/cmj.1968.100859