We show that if G is a connected graph with the same proper convex subgraphs as (Kn)', the Cartesian product of r copies of Kn, r >t 2, n >t 3, then [V(G)I ~> n" with equality if and only if G is isomorphic to (Kn)'. In this note we consider only connected finite undirected simple graphs. The compl
Complete subgraphs of the graphs of convex polytopes
β Scribed by S. Gallivan; E.R. Lockeberg; P. McMullen
- Publisher
- Elsevier Science
- Year
- 1981
- Tongue
- English
- Weight
- 631 KB
- Volume
- 34
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
β¦ Synopsis
It is shown that if three vertices of the graph c?(l)) of a convex 3-polytope P are chosen, then G(P) contains a refinement of the complete graph C,, on four vertices, for which the three chosen vertices are principal (that is, correspond to vertices of C, in the refinement.. In general, all four vertices may not be preassigned as principal. For dimensiorls d 24, simple (simplicial) d-polytopes are constructed whcrre graphs contain sets of three (four) vertices, which cannot all be principal in any refinement of Cd+,.
π SIMILAR VOLUMES
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