Title
A problem of Erdős on the minimum number of k-cliques
Abstract
Fifty years ago Erdos asked to determine the minimum number of k-cliques in a graph on n vertices with independence number less than l. He conjectured that this minimum is achieved by the disjoint union of l-1 complete graphs of size nl-1. This conjecture was disproved by Nikiforov, who showed that the balanced blow-up of a 5-cycle has fewer 4-cliques than the union of 2 complete graphs of size n2. In this paper we solve Erdos@? problem for (k,l)=(3,4) and (k,l)=(4,3). Using stability arguments we also characterize the precise structure of extremal examples, confirming Erdos@? conjecture for (k,l)=(3,4) and showing that a blow-up of a 5-cycle gives the minimum for (k,l)=(4,3).
Year
DOI
Venue
2013
10.1016/j.jctb.2013.02.003
J. Comb. Theory, Ser. B
Keywords
DocType
Volume
complete graph,balanced blow-up,size n2,disjoint union,size nl-1,l-1 complete graph,extremal example,minimum number,independence number,fewer 4-cliques
Journal
103
Issue
ISSN
Citations 
3
0095-8956
8
PageRank 
References 
Authors
0.58
8
5
Name
Order
Citations
PageRank
Shagnik Das1326.57
Hao Huang2589104.49
Jie Ma37815.04
Humberto Naves4244.08
Benny Sudakov51391159.71