Ansong Ma

collaborators

3 papers

math.CO2024

Degree conditions for disjoint path covers in digraphs

Ansong Ma, Yuefang Sun

In this paper, we study degree conditions for three types of disjoint directed path cover problems: many-to-many $k$ -DDPC, one-to-many $k$ -DDPC and one-to-one $k$ -DDPC, which are i…

math.CO2022

A minimum semi-degree condition for unpaired many-to-many disjoint path covers in digraphs

Ansong Ma, Yuefang Sun

For a digraph $D$ , let $δ^{0} (D) = min {δ^{+} (D), δ^{-} (D)}$ be the minimum semi-degree of $D$ . A set of $k$ vertex-disjoint paths, ${P_{1}, \dots, P_{k}}$ , joining a disjoint…

math.CO2022

A minimum semi-degree sufficient condition for one-to-many disjoint path covers in semicomplete digraphs

Ansong Ma, Yuefang Sun, Xiaoyan Zhang

Let $D$ be a digraph. We define the minimum semi-degree of $D$ as $δ^{0} (D) := min {δ^{+} (D), δ^{-} (D)}$ . Let $k$ be a positive integer, and let $S = {s}$ and $T = \{t_{1}, \d…