99 Bottles of Beer
20th
Arabic to Roman
Christmas Trees
13th
Cubes
6th
Diamonds
9th
Divisors
1st64th
Emirp Numbers
24th
Evil Numbers
45th
Fibonacci
Fizz Buzz
30th
Happy Numbers
Leap Years
21st
Leyland Numbers
20th
Niven Numbers
41st
Odious Numbers
42nd
Ordinal Numbers
21st
Pangram Grep
21st
Pascal’s Triangle
28th
Pernicious Numbers
41st
Prime Numbers
47th
Quine
69th