Choosability of Squares of K4-minor Free Graphs
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چکیده
Lih, Wang and Zhu [Discrete Math. 269 (2003), 303–309] proved that the chromatic number of the square of a K4-minor free graph with maximum degree ∆ is bounded by ⌊3∆/2⌋+1 if ∆ ≥ 4, and is at most ∆+3 for ∆ ∈ {2, 3}. We show that the same bounds hold for the list chromatic number of squares of K4-minor free graphs. The same result was also proved independently by Hetherington and Woodall.
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تاریخ انتشار 2008