$ \begin{array}{r|l} 18 & 2\\ 9 & 3\\ 3 & 3\\ 1 & \end{array} $
$18 = 2 * 3^2$

$ \begin{array}{r|l} 40 & 2\\ 20 & 2\\ 10 & 2\\ 5 & 5\\ 1 & \end{array} $
$40 = 2^3 * 5$

$ \begin{array}{r|l} 130 & 2\\ 65 & 5\\ 13 & 13\\ 1 & \end{array} $
$130 = 2 * 5 * 13$

$ \begin{array}{r|l} 210 & 2\\ 105 & 5\\ 21 & 7\\ 3 & 3\\ 1 & \end{array} $
$210 = 2 * 3 * 5 * 7$