99 Bottles of Beer
21st
Abundant Numbers
29th
Christmas Trees
30th
Divisors
33rd
Emirp Numbers
22nd
Evil Numbers
46th
Fibonacci
81st
Fizz Buzz
158th
Leap Years
50th
Morse Decoder
10th
Morse Encoder
9th
Niven Numbers
30th
Odious Numbers
42nd
Ordinal Numbers
27th
Pascal’s Triangle
22nd
Prime Numbers
28th
Roman to Arabic
29th
Seven Segment
19th
π
41st