MathDB

123

Part of 1969 All Soviet Union Mathematical Olympiad

Problems(1)

ASU 123 All Soviet Union MO 1969 airlines connecting cities

Source:

6/23/2019
Every city in the certain state is connected by airlines with no more than with three other ones, but one can get from every city to every other city changing a plane once only or directly. What is the maximal possible number of the cities?
combinatorics