The Ramsey numbers for cycles versus wheels of odd order
β Scribed by Yaojun Chen; T.C. Edwin Cheng; Zhengke Miao; C.T. Ng
- Publisher
- Elsevier Science
- Year
- 2009
- Tongue
- English
- Weight
- 267 KB
- Volume
- 22
- Category
- Article
- ISSN
- 0893-9659
No coin nor oath required. For personal study only.
β¦ Synopsis
For two given graphs G 1 and G 2 , the Ramsey number R(G 1 , G 2 ) is the smallest integer n such that for any graph G of order n, either G contains G 1 or the complement of G contains G 2 . Let C n denote a cycle of order n and W m a wheel of order m + 1. It is conjectured by Surahmat, E.T. Baskoro and I. Tomescu that R(C n , W m ) = 2n -1 for even m β₯ 4, n β₯ m and (n, m) = (4, 4). In this paper, we confirm the conjecture for n β₯ 3m/2 + 1.
π SIMILAR VOLUMES
We prove that the chromatic Ramsey number of every odd wheel W 2k+1 , k β₯ 2 is 14. That is, for every odd wheel W 2k+1 , there exists a 14-chromatic graph F such that when the edges of F are two-coloured, there is a monochromatic copy of W 2k+1 in F, and no graph F with chromatic number 13 has the s
## Abstract Let __r__~__k__~(__G__) be the __k__βcolor Ramsey number of a graph __G__. It is shown that $r\_{k}(C\_{5})\le \sqrt{18^{k}\,k!}$ for __k__β©Ύ2 and that __r__~__k__~(__C__~2__m__+ 1~)β©½(__c__^__k__^__k__!)^1/__m__^ if the Ramsey graphs of __r__~__k__~(__C__~2__m__+ 1~) are not far away fr
As usual, for simple graphs G and H, let the Ramsey number r(G,H) be defined as the least number n such that for any graph K of order n, either G is a subgraph of K or H is a subgraph of/(. We shall establish the values of r(aC~,bCs) and r(aCv, bC7) almost precisely (where nG is the graph consisting