Linear arboricity of an embedded graph on a surface of large genus
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摘要: 通过度再分配的方法研究嵌入到曲面上图的线性荫度. 给定较大亏格曲面\,$\Sigma$\,上嵌入图\,$G$, 如果最大度\, $\Delta(G)\geq (\sqrt{45-45\varepsilon}+10)$\,且不含\,4-圈, 则其线性荫度为\,$\lceil \frac{\Delta}{2}\rceil$, 其中若\,$\Sigma$\, 是亏格为\,$h(h1)$\,的可定向曲面时 $\varepsilon=2-2h$, 若\, $\Sigma$\,是亏格为\,$k(k2)$\,的不可定向曲面时 $\varepsilon=2-k$. 改进了吴建良的结果, 作为应用证明了边数较少图的线形荫度.Abstract: The linear arboricity of a graph $G$ is the minimum number of linear forests which partition the edges of $G$. This paper proved that if $G$ can be embedded on a surface of large genus without 4-cycle and $\Delta(G)\geq (\sqrt{45-45\varepsilon}+10)$, then its linear arboricity is $\lceil \frac{\Delta}{2}\rceil$, where $\varepsilon=2-2h$ if the orientable surface with genus \,$h(h1)$\,or $\varepsilon=2-k$ if the nonorientable surface with genus \,$k(k2)$. It improves the bound obtained by J. L. Wu. As an application, the linear arboricity of a graph with fewer edges were concluded.
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Key words:
- linear arboricity /
- surface /
- embedded graph /
- Euler characteristic
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