In this paper, we introduce a measure of the extent to which a finite combinatorial structure is a Ramsey object in the class of objects with a similar structure. We show for classes of finite relational structures, including graphs, binary posets, and bipartite graphs, how this measure depends on t
Symmetry and the Ramsey degree of posets
✍ Scribed by W.L. Fouché
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 335 KB
- Volume
- 167-168
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
✦ Synopsis
In this paper we introduce a measure of the extent to which a given finite poset deviates from being a Ramsey object in the class of finite posets. We show how this measure depends on the symmetry properties of a poset. containing a copy of Q, an r-colouring of [R, P] can be found which assumes, on any set of the form [Q',P], with Q' a copy of Q in R, at least t(P) values.
📜 SIMILAR VOLUMES
## Abstract We write __H__ → __G__ if every 2‐coloring of the edges of graph __H__ contains a monochromatic copy of graph __G__. A graph __H__ is __G__‐__minimal__ if __H__ → __G__, but for every proper subgraph __H__′ of __H__, __H__′ ↛ __G__. We define __s__(__G__) to be the minimum __s__ such th
## Abstract We investigate the minimization problem of the minimum degree of minimal Ramsey graphs, initiated by Burr et al. We determine the corresponding graph parameter for numerous bipartite graphs, including bi‐regular bipartite graphs and forests. We also make initial progress for graphs of l
We consider the class P n of labeled posets on n elements which avoid certain three-element induced subposets. We show that the number of posets in P n is (n+1) n&1 by exploiting a bijection between P n and the set of regions of the arrangement of hyperplanes in R n of the form x i &x j =0 or 1 for