A sufficient condition for oriented graphs to be Hamiltonian
نویسندگان
چکیده
منابع مشابه
A new sufficient condition for hamiltonian graphs
The study of Hamiltonian graphs began with Dirac’s classic result in 1952. This was followed by that of Ore in 1960. In 1984 Fan generalized both these results with the following result: If G is a 2-connected graph of order n and max{d(u), d(v)}≥n/2 for each pair of vertices u and v with distance d(u, v)=2, then G is Hamiltonian. In 1991 Faudree–Gould–Jacobson–Lesnick proved that if G is a 2-co...
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Let G be a graph and α(G) be the independence number of G. For a vertex v ∈ V (G), d(v) and N(v) represent the degree of v and the neighborhood of v in G, respectively. In this paper, we prove that if G is a k-connected graph of order n, and if max{d(v) : v ∈ S} ≥ n/2 for every independent set S of G with |S| = k which has two distinct vertices x, y ∈ S satisfying 1 ≤ |N(x) ∩N(y)| ≤ α(G)− 1, th...
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Given a 2-connected graph G on n vertices, let G∗ be its partially square graph, obtained by adding edges uv whenever the vertices u, v have a common neighbor x satisfying the condition NG(x) ⊆ NG[u] ∪ NG[v], where NG[x] = NG(x) ∪ {x}. In particular, this condition is satisfied if x does not center a claw (an induced K1,3). Clearly G ⊆ G∗ ⊆ G, where G is the square of G. For any independent tri...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1986
ISSN: 0012-365X
DOI: 10.1016/0012-365x(86)90141-x