A remark on star-C4 and wheel-C4 Ramsey numbers
نویسندگان
چکیده
Given two graphs G1 and G2, the Ramsey number R(G1, G2) is the smallest integer N such that, for any graph G of order N , either G1 is a subgraph of G, or G2 is a subgraph of the complement of G. Let Cn denote a cycle of order n, Wn a wheel of order n + 1 and Sn a star of order n. In this paper, it is shown that R(Wn, C4) = R(Sn+1, C4) for n ≥ 6. Based on this result and Parsons’ results on R(Sn+1, C4), we establish the best possible general upper bound for R(Wn, C4) and determine some exact values for R(Wn, C4).
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عنوان ژورنال:
- EJGTA
دوره 2 شماره
صفحات -
تاریخ انتشار 2014