friendship(KgNM2010)
Source:
April 25, 2011
combinatoricsgraph theoryvertex degree
Problem Statement
At the meeting, each person is familiar with 22 people. If two persons and know each with one another, among the remaining people they do not have a common friend. For each pair individuals and are not familiar with each other, there are among the remaining six common acquaintances. How many people were at the meeting?