MathDB

In a plane, there are

n \geq 3

circular beer mats

B_{1}, B_{2}, ..., B_{n}

of equal size.

B_{k}

touches

B_{k+1}

(

k=1,2,...,n

);

B_{n+1}=B_{1}

. The beer mats are placed such that another beer mat

B

of equal size touches all of them in the given order if rolling along the outside of the chain of beer mats. How many rotations

B

makes untill it returns to it's starting position¿

Problem Statement