Citation: | Xiaoxue Hu, Jiangxu Kong, Yiqiao Wang. LINEAR 2-ARBORICITY OF PLANAR GRAPHS WITH MAXIMUM DEGREE NINE[J]. Journal of Applied Analysis & Computation, 2021, 11(4): 2193-2210. doi: 10.11948/20200448 |
The linear 2-arboricity la$_2(G)$ of a graph $G$ is the least integer $k$ such that $G$ can be partitioned into $k$ edge-disjoint forests, whose component trees are paths of length at most 2. In this paper, we show that every planar graph $G$ with maximum degree $\Delta=9$ has la$_2(G)\le 8$, which extends a known result that every planar graph $G$ with $\Delta\ge10$ has la$_2(G)\le \Delta-1$.
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