Ohba's conjecture for graphs with independence number five
نویسندگان
چکیده
Ohba has conjectured that if G is a k-chromatic graphwith at most 2k+1 vertices, then the list chromatic number or choosability ch(G) of G is equal to its chromatic number χ(G), which is k. It is known that this holds if G has independence number at most three. It is proved here that it holds if G has independence number at most five. In particular, and equivalently, it holds if G is a complete k-partite graph and each part has at most five vertices. © 2011 Elsevier B.V. All rights reserved.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 311 شماره
صفحات -
تاریخ انتشار 2011