Citation: | Xiaoxue Hu, Juan Liu, Yiqiao Wang. AN IMPROVED UPPER BOUND ON THE LINEAR 2-ARBORICITY OF TOROIDAL GRAPHS[J]. Journal of Applied Analysis & Computation, 2022, 12(4): 1672-1678. doi: 10.11948/20220107 |
The linear $ 2 $-arboricity $ {\rm la}_2(G) $ of a graph $ G $ is the smallest integer $ k $ such that $ G $ can be partitioned into $ k $ edge-disjoint forests, whose components are paths of length at most 2. In this paper, we prove that every toroidal graph $ G $ has la$ _{2}(G)\leq \big\lceil\frac{\Delta(G)+1}{2}\big\rceil + 6 $. Since $ K_7 $ is a toroidal graph with la$ _2(K_7)=6=\big\lceil\frac{\Delta(K_7)+1}{2}\big\rceil + 2 $, our solution is within four from optimal.
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