Topological obstructions to fatness
نویسندگان
چکیده
منابع مشابه
Topological Obstructions to Graph Colorings
For any two graphs G and H Lovász has defined a cell complex Hom (G,H) having in mind the general program that the algebraic invariants of these complexes should provide obstructions to graph colorings. Here we announce the proof of a conjecture of Lovász concerning these complexes with G a cycle of odd length. More specifically, we show that If Hom (C2r+1, G) is k-connected, then χ(G) ≥ k + 4....
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ژورنال
عنوان ژورنال: Geometry & Topology
سال: 2011
ISSN: 1364-0380,1465-3060
DOI: 10.2140/gt.2011.15.891