12 Days of Christmas
            
                        
                    24th
        
            Abundant Numbers
            
                        
                    32nd
        
            Christmas Trees
            
                        
                    25th
        
            Divisors
            
                        
                    28th
        
            Emirp Numbers
            
                        
                    13th
        
            Evil Numbers
            
                        
                    36th
        
            Fibonacci
            
                        
                    74th
        
            Fizz Buzz
            2,342nd131st
        
            Happy Numbers
            
                        
                    32nd
        
            Leap Years
            
                        
                    42nd
        
            Morse Decoder
            
                        
                    7th
        
            Morse Encoder
            
                        
                    8th
        
            Niven Numbers
            
                        
                    40th
        
            Odious Numbers
            
                        
                    36th
        
            Ordinal Numbers
            
                        
                    15th
        
            Pangram Grep
            
                        
                    31st
        
            Pascal’s Triangle
            
                        
                    19th
        
            Pernicious Numbers
            
                        
                    35th
        
            Prime Numbers
            
                        
                    20th
        
            Seven Segment
            
                        
                    9th
        
            Spelling Numbers
            
                        
                    7th