MathDB

10.3

Part of 2003 All-Russian Olympiad Regional Round

Problems(1)

45 in alumni meeting - All-Russian MO 2003 Regional (R4) 10.3

Source:

9/17/2024
4545 people came to the alumni meeting. It turned out that any two of them, having the same number of acquaintances among those who came, don't know each other. What is the greatest number of pairs of acquaintances that could to be among those participating in the meeting?
combinatorics