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arXiv 2203.01088math.CO
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图的真无冲突染色的注记

Remarks on proper conflict-free colorings of graphs

Yair Caro, Mirko Petruševski, Riste Škrekovski

摘要:

一个图的顶点染色称为关于邻域的\textit{conflict-free},如果对于每个非孤立顶点,在其(开)邻域中有一种颜色只出现一次。如[Fabrici等人,\textit{Proper Conflict-free and Unique-maximum Colorings of Planar Graphs with Respect to Neighborhoods},arXiv preprint]中,图$G$的任何这样的适当着色中的颜色的最小数目是$G$的PCF色数,记为$χ_{\mathrm{pcf}}(G)$。本文对树、圈、超立方体和完全图的剖分等几类基本图确定了这个图参数的值。我们也给出了$χ_{\mathrm{pcf}}(G)$的上界的其他图参数。特别是,我们表明,$χ_{\mathrm{pcf}}(G) \leq5Δ(G)/2$和表征平等。对$4\le k\le 6$建立了图的PCF $k$ -可染性的几个充分条件.本文的结论与几个开放的问题。

英文摘要:

A vertex coloring of a graph is said to be \textit{conflict-free} with respect to neighborhoods if for every non-isolated vertex there is a color appearing exactly once in its (open) neighborhood. As defined in [Fabrici et al., \textit{Proper Conflict-free and Unique-maximum Colorings of Planar Graphs with Respect to Neighborhoods}, arXiv preprint], the minimum number of colors in any such proper coloring of graph $G$ is the PCF chromatic number of $G$, denoted $χ_{\mathrm{pcf}}(G)$. In this paper, we determine the value of this graph parameter for several basic graph classes including trees, cycles, hypercubes and subdivisions of complete graphs. We also give upper bounds on $χ_{\mathrm{pcf}}(G)$ in terms of other graph parameters. In particular, we show that $χ_{\mathrm{pcf}}(G) \leq5Δ(G)/2$ and characterize equality. Several sufficient conditions for PCF $k$-colorability of graphs are established for $4\le k\le 6$. The paper concludes with few open problems.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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