On spanning k-tree in which specified vertices have degree less than k
نویسنده
چکیده
A k-tree is a tree with maximum degree at most k. In this paper, we give a degree sum condition for a graph to have a spanning k-tree in which specified vertices have degree less than k. We denote by σk(G) the minimum value of the degree sum of k independent vertices in a graph G. Let k ≥ 3 and s ≥ 0 be integers, and suppose G is a connected graph and σk(G) ≥ |V (G)|+s−1. Then for any s specified vertices, G contains a spanning k-tree in which every specified vertex has degree less than k. The degree condition is sharp.
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عنوان ژورنال:
- Discussiones Mathematicae Graph Theory
دوره 35 شماره
صفحات -
تاریخ انتشار 2015