Let Tbe a tournament and let c :e(T)--> {1 ..... r} be an r-colouring of the edges of T. The associated reachability graph, denoted by R(T, c) is a directed graph whose vertices are the vertices of T, and a vertex v of R(T, c) dominates a vertex u of R(T, c) iff there is a monochromatic directed pat
Turán-Ramsey problems
✍ Scribed by Béla Bollobás
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 278 KB
- Volume
- 156
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
✦ Synopsis
For i = 1,2 .... ,k, let Gi be a graph with vertex set [n] = {1 .... ,n} containing no Fi as a subgraph. At most how many edges are in G1 t3 -• • U Gk? We shall answer this Turfin-Ramseytype question asymptotically, and pose a number of related problems.
Given graphs F1 ..... Fk, write exk(n,F 1 ..... Fk) for the maximal size of a graph
📜 SIMILAR VOLUMES
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## Abstract For each __n__ and __k__, we examine bounds on the largest number __m__ so that for any __k__‐coloring of the edges of __K~n~__ there exists a copy of __K~m~__ whose edges receive at most __k−__1 colors. We show that for $k \ge \sqrt{n}\;+\,\Omega(n^{1/3})$, the largest value of __m__ i
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We consider the following analogue of a problem of Turin for interval graphs: Let c = c(n, rn) be the largest integer such that any interval graph with n vertices and at least m edges contains a complete subgraph on c vertices. We determine the value of c(n, m) explicitly.