(20, 12)
          ( 4 )

(20, 16)
          (    )

(18, 12)
          (    )

(24, 20)
          (    )

(3, 18)
          (    )

(15, 6)
          (    )

(4, 4)
          (    )

(30, 5)
          (    )

(16, 12)
          (    )

        +[    ]

(24, 30)
          (    )

(24, 20)
          (    )

(4, 8)
          (    )

(20, 12)
          (    )

(12, 10)
          (    )

(4, 10)
          (    )

(25, 30)
          (    )

(9, 6)
          (    )

(15, 18)
          (    )

        +[    ]

(12, 9)
          (    )

(10, 15)
          (    )

(4, 10)
          (    )

(24, 20)
          (    )

(9, 6)
          (    )

(10, 6)
          (    )

(30, 12)
          (    )

(2, 6)
          (    )

(8, 20)
          (    )

        +[    ]

(6, 3)
          (    )

(12, 2)
          (    )

(18, 12)
          (    )

(2, 6)
          (    )

(8, 12)
          (    )

(10, 15)
          (    )

(5, 30)
          (    )

(24, 18)
          (    )

(12, 15)
          (    )

        +[    ]

(10, 15)
          (    )

(20, 5)
          (    )

(8, 10)
          (    )

(25, 20)
          (    )

(20, 4)
          (    )

(30, 6)
          (    )

(2, 10)
          (    )

(15, 5)
          (    )

(8, 12)
          (    )

        +[    ]

  ++[[       ]]

(20, 12)
          ( 4 )
(20, 16)
          ( 4 )
(18, 12)
          ( 6 )
(24, 20)
          ( 4 )
(3, 18)
          ( 3 )
(15, 6)
          ( 3 )
(4, 4)
          ( 4 )
(30, 5)
          ( 5 )
(16, 12)
          ( 4 )
        +[    ]

(24, 30)
          ( 6 )
(24, 20)
          ( 4 )
(4, 8)
          ( 4 )
(20, 12)
          ( 4 )
(12, 10)
          ( 2 )
(4, 10)
          ( 2 )
(25, 30)
          ( 5 )
(9, 6)
          ( 3 )
(15, 18)
          ( 3 )
        +[    ]

(12, 9)
          ( 3 )
(10, 15)
          ( 5 )
(4, 10)
          ( 2 )
(24, 20)
          ( 4 )
(9, 6)
          ( 3 )
(10, 6)
          ( 2 )
(30, 12)
          ( 6 )
(2, 6)
          ( 2 )
(8, 20)
          ( 4 )
        +[    ]

(6, 3)
          ( 3 )
(12, 2)
          ( 2 )
(18, 12)
          ( 6 )
(2, 6)
          ( 2 )
(8, 12)
          ( 4 )
(10, 15)
          ( 5 )
(5, 30)
          ( 5 )
(24, 18)
          ( 6 )
(12, 15)
          ( 3 )
        +[    ]

(10, 15)
          ( 5 )
(20, 5)
          ( 5 )
(8, 10)
          ( 2 )
(25, 20)
          ( 5 )
(20, 4)
          ( 4 )
(30, 6)
          ( 6 )
(2, 10)
          ( 2 )
(15, 5)
          ( 5 )
(8, 12)
          ( 4 )
        +[    ]

  ++[[       ]]