Closure for Spanning Trees with k-Ended Stems

Abstract

Let T be a tree. The set of leaves of Τ is denoted by Leaf(Τ). The subtree Τ—Leaf(Τ) of T is called the stem of Τ. A stem is called a k-ended stem if it has at most k-leaves in it. In this paper, we prove the following theorem. Let G be a connected graph and k≥2 be an integer. Let u and ν be a pair of nonadjacent vertices in G. Suppose that |NG(u)∪NG(v)|≥|G|-k-1. Then G has a spanning tree with k-ended stem if and only if G+uv has a spanning tree with k-ended stem. Moreover, the condition on |NG(u)∪NG(v)| is sharp.

Keywords

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Yan, Z. (2014) Closure for Spanning Trees with k-Ended Stems. Open Journal of Discrete Mathematics, 4, 55-59. doi: 10.4236/ojdm.2014.43008.

Conflicts of Interest

The authors declare no conflicts of interest.

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