On $n$ numbers on a circle

Let $[a_1(0),\ldots,a_n(0)]$ be a real vector; define recursively $a_i(t+1)=|a_i(t)-a_{(i+1)}(t)|$. This paper is devoted to the study of $[a_1(t),\ldots,a_n(t)]$ for $t$ tending to infinity.