On Spanning Trees with few Branch Vertices, all with degree 3
نویسندگان
چکیده
Let G be a connected claw-free graph. A conjecture of Matsuda, Ozeki, and Yamashita [9] posits the existence of either a spanning tree with few branch vertices or a large independent set of small degree sum. The possible appearances of this minimal spanning tree may be ruled out piecemeal. This paper treats one particular class, which may be the easiest to rule out but also fits, to our knowledge, all proposed sharpness examples.
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