Erdős 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
Extremal problems for directed graphs
✍ Scribed by W.G Brown; P Erdös; M Simonovits
- Publisher
- Elsevier Science
- Year
- 1973
- Tongue
- English
- Weight
- 858 KB
- Volume
- 15
- Category
- Article
- ISSN
- 0095-8956
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