more than m participants at a camp, friends related
Source: Norwegian Mathematical Olympiad 2003 - Abel Competition p4b
February 21, 2020
combinatorics
Problem Statement
Let be an integer. At a camp there are more than participants. The camp manager discovers that every time he picks out the camp participants, they say they have exactly one mutual friend among the participants. Which is the largest possible number of participants at the camp?
(If is a friend of is also a friend of . A person is not considered a friend of himself.)