12 Days of Christmas
13th
99 Bottles of Beer
8th
Abundant Numbers
16th
brainfuck
Christmas Trees
11th
Cubes
9th
Diamonds
8th
Divisors
18th
Emirp Numbers
31st
Evil Numbers
39th
Fibonacci
18th
101st
Fizz Buzz
9th
Lucky Tickets
Morse Decoder
8th
Niven Numbers
24th
Odious Numbers
33rd
Pangram Grep
13th
Pernicious Numbers
38th
Prime Numbers
54th
United States
18th
π
16th
τ
15th
φ
23rd
√2
30th