A linear $ k $-diforest is a directed forest in which every connected component is a directed path of length at most $ k $. The linear $ k $-arboricity of a digraph $ D $ is the minimum number of arc-disjoint linear $ k $-diforests whose union covers all the arcs of $ D $. In this paper, we study the linear $ k $-arboricity for symmetric directed trees and fully determine the linear $ 2 $-arboricity for all symmetric directed trees.
Citation: Xiaoling Zhou, Chao Yang, Weihua He. The linear $ k $-arboricity of symmetric directed trees[J]. AIMS Mathematics, 2022, 7(2): 1603-1614. doi: 10.3934/math.2022093
A linear $ k $-diforest is a directed forest in which every connected component is a directed path of length at most $ k $. The linear $ k $-arboricity of a digraph $ D $ is the minimum number of arc-disjoint linear $ k $-diforests whose union covers all the arcs of $ D $. In this paper, we study the linear $ k $-arboricity for symmetric directed trees and fully determine the linear $ 2 $-arboricity for all symmetric directed trees.
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