16

     " " 2    ()
     "3 " 2   (   4   0.7/2)
     "3 " 4    ()
     "3 " 4   (   4   0.7/2)
     "3 " 6    ()
     "3 " 6   (   4   0.7/2)
     "3 " 8   ()
     "3 " 8   (   4   0.7/2)
     "3  " 2    ()
     "3  " 2   (   4   0.7/2)
     "3  " 4  ()
     "3  " 4   (   4   0.7/2)
     "3  " 6   ()
     "3  " 6   (   4   0.7/2)
     "3  " 8   ()
     "3  " 8   (   4   0.7/2)