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