Extremal graph
Source: Mongolian Mathematical Olympiad P5
January 30, 2024
combinatoricsgraph theoryExtremal
Problem Statement
There are students in a class, and some pairs of these students are friends. Among any six students, there are two of them that are not friends, and for any pair of students that are not friends there is a student among the remaining four that is friends with both of them. Find the maximum value of .