Spectral radius and Hamiltonicity of graphs with large minimum degree
نویسنده
چکیده
We extend some recent results on sufficient conditions for Hamiltonian paths and cycles in G. Let G be a graph of order n and λ (G) be the spectral radius of its adjacency matrix. One of the main results of the paper is the following theorem: Let k 2, n k3 + k + 4, and let G be a graph of order n, with minimum degree δ (G) k. If λ (G) n k 1, then G has a Hamiltonian cycle, unless G = K1 _ (Kn k 1+Kk) or G = Kk _ (Kn 2k+Kk).
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