Hamiltonicity of Cubic 3-Connected k-Halin Graphs
نویسندگان
چکیده
We investigate here how far we can extend the notion of a Halin graph such that hamiltonicity is preserved. Let H = T ∪ C be a Halin graph, T being a tree and C the outer cycle. A k-Halin graph G can be obtained from H by adding edges while keeping planarity, joining vertices of H − C, such that G − C has at most k cycles. We prove that, in the class of cubic 3-connected graphs, all 14-Halin graphs are hamiltonian and all 7-Halin graphs are 1-edge hamiltonian. These results are best possible.
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ورودعنوان ژورنال:
- Electr. J. Comb.
دوره 20 شماره
صفحات -
تاریخ انتشار 2013