The Ramsey numbers of trees versus W6 or W7
نویسندگان
چکیده
1 Let Tn denote a tree of order n and Wm a wheel of order m+1. In this paper, we show the Ramsey 2 numbers R(Tn , W6) = 2n − 1 + μ for n ≥ 5, where μ = 2 if Tn = Sn, μ = 1 if Tn = Sn(1, 1) or 3 Tn = Sn(1, 2) and n ≡ 0 (mod 3), and μ = 0 otherwise; R(Tn , W7) = 3n − 2 for n ≥ 6. 4 © 2005 Elsevier Ltd. All rights reserved. 5
منابع مشابه
The Ramsey numbers of large trees versus wheels
For two given graphs G1 and G2, the Ramseynumber R(G1,G2) is the smallest integer n such that for anygraph G of order n, either $G$ contains G1 or the complementof G contains G2. Let Tn denote a tree of order n andWm a wheel of order m+1. To the best of our knowledge, only R(Tn,Wm) with small wheels are known.In this paper, we show that R(Tn,Wm)=3n-2 for odd m with n>756m^{10}.
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ورودعنوان ژورنال:
- Eur. J. Comb.
دوره 27 شماره
صفحات -
تاریخ انتشار 2006