Journal or Book Title
Motivated by the work of Razborov about the minimal density of triangles in graphs we study the minimal density of cycles C5. We show that every graph of order n and size (1−1k)(n2), where k≥3 is an integer, contains at least (110−12k+1k2−1k3+25k4)n5+o(n5)
copies of C5. This bound is optimal, since a matching upper bound is given by the balanced complete k-partite graph. The proof is based on the flag algebras framework. We also provide a stability result for 2≤k≤73.
Bennett, Patrick; Dudek, Andrzej; and Lidicky, Bernard, "Minimizing the number of 5-cycles in graphs with given edge-density" (2018). Mathematics Publications. 181.