For n=375494703 holds: 34 = l(2n) < l(n) = 35.
Using the window-method on the binary representation 101100110000110011000001011112 of this value n, it is
easy to construct a star chain of length 35 by hand for n.
But how to construct a shorter chain for the twice of this number?
Finally, we must prove, that l(n)=35 is indeed minimal. This is hard!
To be precise, we should also show that l(2n)=34 is smallest possible.