12 Days of Christmas
31st
99 Bottles of Beer
15th
Arabic to Roman
44th
Christmas Trees
10th
Cubes
8th
Diamonds
9th
Divisors
24th
Emirp Numbers
19th
Evil Numbers
24th
Fibonacci
22nd
Fizz Buzz
14th
Fractions
9th
Leap Years
14th
Odious Numbers
24th
Pernicious Numbers
15th
Quine
1st705th
Sierpiński Triangle
10th
Spelling Numbers
44th
Tongue-twisters
8th
λ
7th