D. Hanh

collaborators

3 papers

math.CO2018

A note on spanning trees of connected $K_{1, t}$ -free graphs whose stems have a few leaves

Pham Hoang Ha, Dang Dinh Hanh

Let $T$ be a tree, a vertex of degree one is called a leaf. The set of leaves of $T$ is denoted by $L e a f (T)$ . The subtree $T - L e a f (T)$ of $T$ is called the stem of $T$ and denoted b…

math.CO2018

Spanning trees with at most 2 branch vertices in claw - free graphs

Pham Hoang Ha, Dang Dinh Hanh

In this article, we will prove that if $G$ is a connected claw-free graph and either $σ_{6} (G) \geq ∣ G ∣ - 5$ or $σ_{7} (G) \geq ∣ G ∣ - 2$ , here $σ_{k} (G)$ is the minimmum degree sum of $k$ indep…

math.CO2018

Spanning trees with at most 4 leaves in $K_{1, 5} -$ free graphs

Yuan Chen, Pham Hoang Ha, Dang Dinh Hanh

In 2009, Kyaw proved that every $n$ -vertex connected $K_{1, 4}$ -free graph $G$ with $σ_{4} (G) \geq n - 1$ contains a spanning tree with at most $3$ leaves. In this paper, we prove an ana…

A note on spanning trees of connected K1,t​-free graphs whose stems have a few leaves

Spanning trees with at most 2 branch vertices in claw - free graphs

Spanning trees with at most 4 leaves in K1,5​−free graphs

A note on spanning trees of connected $K_{1, t}$ -free graphs whose stems have a few leaves

Spanning trees with at most 4 leaves in $K_{1, 5} -$ free graphs