Problem

Source: INAMO Shortlist 2015 C5

Tags: combinatorics, max



A meeting was attended by $n$ people. They are welcome to occupy the $k$ table provided $\left( k \le \frac{n}{2} \right)$. Each table is occupied by at least two people. When the meeting begins, the moderator selects two people from each table as representatives for talk to. Suppose that $A$ is the number of ways to choose representatives to speak. Determine the maximum value of $A$ that is possible.