Chromatic number, independence ratio, and crossing number
نویسندگان
چکیده
منابع مشابه
On the chromatic number and independence number of hypergraph products
The hypergraph product G2H has vertex set V (G) × V (H), and edge set {e × f : e ∈ E(G), f ∈ E(H)}, where × denotes the usual cartesian product of sets. We construct a hypergraph sequence {Gn} for with χ(Gn) → ∞ and χ(Gn2Gn) = 2 for all n. This disproves a conjecture of Berge and Simonovits [2]. On the other hand, we show that if G and H are hypergraphs with infinite chromatic number, then the ...
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ژورنال
عنوان ژورنال: Ars Mathematica Contemporanea
سال: 2008
ISSN: 1855-3974,1855-3966
DOI: 10.26493/1855-3974.10.2d0