Implement the following method. Do not use any local variables or loops.

public static void pattern$($int n$)$

$//$ Precondition: $n>0$;

$//$ Postcondition: The output consists of lines of integers. The first line

$\frac{\frac{?}{?}}{?}$ is the number n $.$ The next line is the number $2$ n $.$ The next line is

$//$ the number $4$ n $,$ and so on until you reach a number that is larger than

$//4242.$ This list of numbers is then repeated backward until you get back

$//$ to n$.$

$/*$ Example output with $n=840$ :

$840$

$1680$

$3360$

$6720$

$6720$

$3360$

$1680$

$840$