Numerateurs:Denominateurs                                                                           
                                                                                                                        
                    1:1   1:2---1:3   1:4   1:5   (...)                                                                 
                     |    /     /                                                                                       
                     |  /     /                                                                                         
                     |/     /                                                                                           
                    2:1   2:2   2:3   2:4   2:5   (...)                                                                 
                          /                                                                                             
                        /                                                                                               
                      /                                                                                                 
                    3:1   3:2   3:3   3:4   3:5   (...)                                                                 
                                                                                                                        
                                                                                                                        
                                                                                                                        
                    4:1   4:2   4:3   4:4   4:5   (...)                                                                 
                                                                                                                        
                                                                                                                        
                                                                                                                        
                    5:1   5:2   5:3   5:4   5:5   (...)                                                                 
                            .     .     .     .                                                                         
                            .     .     .     .                                                                         
                            .     .     .     .                                                                         
                                                                                                                        
                    (...)                                                                                               
                                                                                                                        
                                                                                                                        
                                                                                                                        
                    {1/1, 2/1, 1/2, 1/3, 2/2, 3/1,                                                        }             
                      |                   |                                                                             
                       -------------------                                                                              
                                                                                                                        
                                                                                                                        
                                                                                                                        
                                                                                                                        
                                                                                                                        
                                                                                                                        
                                                                                                                        
                     -------------------------------------------------------------------------------------              
                    |                                                                                     |             
                    |  1/1  2/1  1/2  1/3       3/1                                                       |             
                    |   |    |    |    |         |                                                        |             
                     -------------------------------------------------------------------------------------              
                        |    |    |    |         |                                                                      
                        |    |    |    |         |                                                                      
                        |    |    |    |         |                                                                      
                     -------------------------------------------------------------------------------------              
                    |   |    |    |    |         |                                                        |             
                    |   1    2    3    4         5                                                        |             
                    |                                                                                     |             
                     -------------------------------------------------------------------------------------              
                                                                                                                        
                                                                                                                        
 JFC                                                                                                                    
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