12 Days of Christmas
16th
Abundant Numbers
51st
35th
Arabic to Roman
15th
Divisors
1st
1st
Emirp Numbers
268th
75th
Evil Numbers
373rd
57th
Fibonacci
166th
7th
Fizz Buzz
54th
1st
Happy Numbers
165th
24th
Leap Years
207th
45th
Look and Say
87th
8th
Niven Numbers
182nd
28th
Odious Numbers
275th
49th
Pangram Grep
25th
Pernicious Numbers
304th
54th
Prime Numbers
145th
Quine
1st105th63rd22nd71st
Recamán
201st
18th
Roman to Arabic
39th
π
26th