Abstract
An edge of a k-connected graph is said to be k-contractible if its contraction results in a k-connected graph. A k-connected non-complete graph with no k-contractible edge, is called contraction critical k-connected. Let G be a contraction critical 5-connected graph, in this paper we show that G has at least \({\frac{1}{2}|G|}\) vertices of degree 5.
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Li, T., Su, J. The New Lower Bound of the Number of Vertices of Degree 5 in Contraction Critical 5-Connected Graphs. Graphs and Combinatorics 26, 395–406 (2010). https://doi.org/10.1007/s00373-010-0907-z
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DOI: https://doi.org/10.1007/s00373-010-0907-z