12 Days of Christmas
            
                        
                    5th
                        
                    
                        
                    
        
            99 Bottles of Beer
            
                        
                    10th
                        
                    
                        
                    
        
            Abundant Numbers
            
                        
                    12th
                        
                    
                        
                    
        
            Abundant Numbers (Long)
            
                        
                    8th
                        
                    
                        
                    
        
            Arabic to Roman
            
                        
                    1st
                        
                    
                        
                    
        
            Arithmetic Numbers
            
                        
                    9th
                        
                    
                        
                    
        
            ASCII Table
            
                        
                    6th
                        
                    
                        
                    
        
            Card Number Validation
            
                        
                    2nd
                        
                    
                        
                    
        
            Catalan Numbers
            
                        
                    13th
                        
                    
                        
                    
        
            Christmas Trees
            
                        
                    6th
                        
                    
                        
                    
        
            Collatz
            
                        
                    12th
                        
                    14th
        
            CSS Colors
            
                        
                    4th
                        
                    
                        
                    
        
            Day of Week
            
                        
                    1st
                        
                    
                        
                    
        
            Diamonds
            
                        
                    6th
                        
                    
                        
                    
        
            Divisors
            
                        
                    5th
                        
                    21st
        
            Emirp Numbers
            
                        
                    19th
                        
                    
                        
                    
        
            Emirp Numbers (Long)
            
                        
                    7th
                        
                    
                        
                    
        
            Evil Numbers
            
                        
                    16th
                        
                    
                        
                    
        
            Evil Numbers (Long)
            
                        
                    13th
                        
                    
                        
                    
        
            Fibonacci
            81st1st
                        
                    41st
        
            Fizz Buzz
            
                        
                    11th
                        
                    43rd
        
            Fractions
            
                        
                    1st
                        
                    
                        
                    
        
            Happy Numbers
            
                        
                    17th
                        
                    
                        
                    
        
            Inventory Sequence
            
                        
                    7th
                        
                    
                        
                    
        
            ISBN
            
                        
                    9th
                        
                    
                        
                    
        
            Jacobi Symbol
            
                        
                    8th
                        
                    
                        
                    
        
            Leap Years
            
                        
                    13th
                        
                    
                        
                    
        
            Levenshtein Distance
            
                        
                    1st
                        
                    
                        
                    
        
            Look and Say
            
                        
                    7th
                        
                    
                        
                    
        
            Niven Numbers
            
                        
                    17th
                        
                    35th
        
            Niven Numbers (Long)
            
                        
                    13th
                        
                    
                        
                    
        
            Odious Numbers
            
                        
                    16th46th
                        
                    
        
            Odious Numbers (Long)
            
                        
                    13th
                        
                    
                        
                    
        
            Ordinal Numbers
            
                        
                    8th
                        
                    
                        
                    
        
            PalindromemordnilaP
            
                        
                    3rd
                        
                    
                        
                    
        
            Pangram Grep
            
                        
                    11th
                        
                    
                        
                    
        
            Pascal’s Triangle
            
                        
                    5th
                        
                    
                        
                    
        
            Pernicious Numbers
            
                        
                    13th
                        
                    
                        
                    
        
            Pernicious Numbers (Long)
            
                        
                    13th
                        
                    
                        
                    
        
            Prime Numbers
            
                        
                    1st
                        
                    
                        
                    
        
            Prime Numbers (Long)
            
                        
                    1st
                        
                    
                        
                    
        
            Recamán
            
                        
                    6th
                        
                    
                        
                    
        
            Reverse Polish Notation
            
                        
                    1st
                        
                    
                        
                    
        
            Rijndael S-box
            
                        
                    6th
                        
                    
                        
                    
        
            Roman to Arabic
            
                        
                    1st
                        
                    
                        
                    
        
            Sierpiński Triangle
            
                        
                    6th
                        
                    
                        
                    
        
            Smith Numbers
            
                        
                    7th
                        
                    
                        
                    
        
            Tongue-twisters
            
                        
                    11th
                        
                    
                        
                    
        
            Transpose Sentence
            
                        
                    7th
                        
                    
                        
                    
        
            Van Eck Sequence
            
                        
                    7th
                        
                    
                        
                    
        
            √2
            
                        
                    9th
                        
                    
                        
                    
        
            𝑒
            
                        
                    6th