How many rounds in a tournament with n players I am stuck on the following question...
Suppose n people are playing in a tournament where n is a power of two so that it creates an even bracket. 
In the first round each player is paired with another player, only the winner of each pair go on to the next round. 
How many rounds will there be in the tournament until it finishes?
I have to create an equation in terms of n but I have been messing around with some numbers and can't figure this one out.

If the people are $n=2^k$, to finish you need $k$ rounds (only one winner remains).
EG
$$n=16=2^4$$


*

*after first round $\to$ 8 people

*after second round $\to$ 4 people

*after third round $\to$ 2 people

*after forth round $\to$ 1 winner

