## Abstract We investigate the asymptotics of the size Ramsey number __รฎ__(__K__~1,__n__~__F__), where __K__~1,__n__~ is the __n__โstar and __F__ is a fixed graph. The author 11 has recently proved that __rฬ__(__K__~1,n~,__F__)=(1+__o__(1))__n__^2^ for any __F__ with chromatic number ฯ(__F__)=3. He
Size Ramsey numbers involving stars
โ Scribed by R.J. Faudree; J. Sheehan
- Publisher
- Elsevier Science
- Year
- 1983
- Tongue
- English
- Weight
- 302 KB
- Volume
- 46
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
โฆ Synopsis
We calculate some size Ramsey numbers involving stars. For example we prove that for t ~ k w2 ~md n sufficiently large the size Ramsey number r,, (K,,k
All graphs in this paper are finite, simple and undirected. Let F, C and H be graphs. The number of vertices and edges of a graph F will be denoted by p(F) and q(F) resl~rctively, A graph F---~ (G, Hi if every 2-colouring (say red and blue) of the edges cf F produces either a 'red' G or a 'blue' H. Since all colourings of F below will be 2-colourings of the edges of F we shall simply refer to 'colouring~' of F. The Ramsey number r(G, ]~ = rp(G, H) = min{p(F3:F---~(G, H)}, the size Ramsey number rq( G, H) = min(q(F) : F'-+( G, H)}, and the restricted size Ramsey number
r*( G, H) = min{q( F) : F--) ( G, H), p( lO = r( G, H)}.
Also if H is a ,;ubgraph of G, then G-H will denote the graph obtained from G by deleting the edges of H. Thus both G and G-H will have the same vertex set. P denotes the complement of F. Suppose G and H ;.we distinct (disjoint) graphs. Then G U H is 'their disjoint union and G + H denotes the complement of t~ U/SL
The term 'size. Ramsey numbc~ was introduced in [5] and further studied in [4], [6], [8] and [9].
A survey of the few results concerning this function can be found it. [2]. The
๐ SIMILAR VOLUMES
Caro, Y., On zero-sum Ramsey numbers--stars, Discrete Mathematics 104 (1992) l-6. Let n 3 k 2 2 be positive integers, k ( n. Let H, be the cyclic group of order k. Denote by R(K,,,> Z,) the minimal integer t such that for every &-coloring of the edges of K,, (i.e., a function c : E(K,)+ hk), there i
## Abstract The following result is proved. A graph __G__ can be expressed as the edgeโdisjoint union of __k__ graphs having chromatic numbers no greater than __m__~1~,โฆ,__m__~__k__~, respectively, iff ฯ(__G__) โค __m__~1~โฆ__m__~__k__~.
The Ramsey number r ( G , H ) is evaluated exactly in certain cases in which both G and H are complete multipartite graphs K(n,, n2, ..., n k ) . Specifically, each of the following cases is handled whenever n is sufficiently large: r(K(1, m,, ..., m k ) , K(1, n)), r(K(1, m), K(n,, ..., nk, n)), pr