Spanning trees with at most $5$ leaves and branch vertices in total of $K_{1,5}$-free graphs

Abstract

In this paper, we prove that every $n$-vertex connected $K_{1,5}$-free graph $G$ with $\sigma_4(G)\geq n-1$ contains a spanning tree with at most $5$ leaves and branch vertices in total. Moreover, the degree sum condition "$\sigma_4(G)\geq n-1$" is best possible.