Irreducible Coverings by Cliques and Sperner's Theorem
نویسنده
چکیده
In this note it is proved that if a graph G of order n has an irreducible covering of its vertex set by n− k cliques, then its clique number ω(G) ≤ k + 1 if k = 2 or 3 and ω(G) ≤ ( k bk/2c) if k ≥ 4. These bounds are sharp if n ≥ k + 1 (for k = 2 or 3) and n ≥ k + ( k bk/2c) (for k ≥ 4).
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عنوان ژورنال:
- Electr. J. Comb.
دوره 9 شماره
صفحات -
تاریخ انتشار 2002