## Abstract We derive bounds for __f(v)__, the maximum number of edges in a graph on __v__ vertices that contains neither threeβcycles nor fourβcycles. Also, we give the exact value of __f(v)__ for all __v__ up to 24 and constructive lower bounds for all __v__ up to 200. Β© 1993 John Wiley & Sons, I
On extremal graphs without compatible triangles or quadrilaterals
β Scribed by Olof Barr
- Book ID
- 103060454
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- English
- Weight
- 679 KB
- Volume
- 125
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
β¦ Synopsis
Letf(n, H, 5) be the maximal number of edges in a graph with n vertices not containing a subgraph H compatible with a transition system X in the family of transition systems !T. Here we will use a family of transition systems X,, defined through local edge colourings. At each vertex the edge set is partitioned into parts containing no more than s+ 1 edges. An allowed transition at a vertex is a pair of incident edges not contained in the same part. In this paper we will give upper and lower bounds for f(n, &, X,) and f(n, C4, X,).
π SIMILAR VOLUMES
ErdΕs has conjectured that every subgraph of the n-cube Q n having more than (1/2+o(1))e(Q n ) edges will contain a 4-cycle. In this note we consider 'layer' graphs, namely, subgraphs of the cube spanned by the subsets of sizes k -1, k and k + 1, where we are thinking of the vertices of Q n as being