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SMO 2012 Junior Round 1 Question 35

SMO · SMO 2012 Junior Round 1

Question 35

There are $k$ people and $n$ chairs in a row, where $2\le k\lt n$. Two of the people form a couple. The number of ways to seat all $k$ people with the couple together equals the number of ways to seat the other $k-2$ people without the couple. Find the smallest $n$.