A Dirac-Type Result on Hamilton Cycles in Oriented Graphs
نویسندگان
چکیده
We show that for each α > 0 every sufficiently large oriented graph G with δ(G), δ−(G) ≥ 3|G|/8 + α|G| contains a Hamilton cycle. This gives an approximate solution to a problem of Thomassen [21]. In fact, we prove the stronger result that G is still Hamiltonian if δ(G) + δ(G) + δ−(G) ≥ 3|G|/2 + α|G|. Up to the term α|G| this confirms a conjecture of Häggkvist [10]. We also prove an Ore-type theorem for oriented graphs.
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عنوان ژورنال:
- Combinatorics, Probability & Computing
دوره 17 شماره
صفحات -
تاریخ انتشار 2008