Quadrangularly connected claw-free graphs
نویسندگان
چکیده
A graph G is quadrangularly connected if for every pair of edges e1 and e2 in E(G), G has a sequence of l-cycles (3 ≤ l ≤ 4) C1, C2, ..., Cr such that e1 ∈ E(C1) and e2 ∈ E(Cr) and E(Ci) ∩ E(Ci+1) 6= ∅ for i = 1, 2, ..., r − 1. In this paper, we show that every quadrangularly connected claw-free graph without vertices of degree 1, which does not contain an induced subgraph H isomorphic to either G1 or G2 such that N1(x,G) of every vertex x of degree 4 in H is disconnected is hamiltonian, which implies a result by Z. Ryjác̆ek (J. Graph Theory, 14 (1990), 321-331) and other known results.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 307 شماره
صفحات -
تاریخ انتشار 2007