23                      1                              8                                              15



      20                                 30                               21                                    3           


      4                                                      11



5                                             18                              2                           27



      19                                                                               28                                         

                 16              7                                                                            12
                                           25                   26             

6                                       24                              14      

                         9                                                         13                                   10

22                                        

                                                                                                    17




                                                  29


                                                                    31