2023 AMC 10B Problems/Problem 2
Revision as of 12:17, 13 November 2023 by Rollover2020 (talk | contribs)
There are 2022 users on a social network called Mathbook, and some of them are Mathbook-friends. (On Mathbook, friendship is always mutual and permanent.)
Starting now, Mathbook will only allow a new friendship to be formed between two users if they have at least two friends in common. What is the minimum number of friendships that must already exist so that every user could eventually become friends with every other user?
