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MathNet 2013 Question 86

Math Olympiad Vault · MathNet 2013

Question 86

Some pairs of cities of a country consisting of $100$ cities are connected by $2013$ round trip flights operated by $n$ air companies. There are at least two cities such that one is not reachable from the other one by one or two flights. Given that for any pair of cities there is an air company connecting these two cities by direct or indirect flights, find the maximal possible value of $n$.