How many graphs are unions of k-cliques?
✍ Scribed by Béla Bollobás; Graham R. Brightwell
- Publisher
- John Wiley and Sons
- Year
- 2006
- Tongue
- English
- Weight
- 171 KB
- Volume
- 52
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
We study the number $ F [n;k] $ of n‐vertex graphs that can be written as the edge‐union of k‐vertex cliques. We obtain reasonably tight estimates for $ F [n;k] $ in the cases (i) k = n − o(n) and (ii) k = o(n) but $ k/log, n \to\infty $. We also show that $ F [n;k] $ exhibits a phase transition around $ k = log_2 n $. We leave open several potentially interesting cases, and raise some other questions of a similar nature. © 2006 Wiley Periodicals, Inc. J Graph Theory 52: 87–107, 2006
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