12 Days of Christmas
47th
99 Bottles of Beer
36th
Abundant Numbers
63rd
Arabic to Roman
27th
Christmas Trees
73rd
CSS Colors
34th
Cubes
16th
Diamonds
21st
Divisors
31st
Emirp Numbers
43rd
Evil Numbers
87th
Fibonacci
1st
Fizz Buzz
62nd
Happy Numbers
35th
Kolakoski Sequence
26th
Leap Years
44th
Look and Say
28th
Niven Numbers
50th
Odious Numbers
66th
Ordinal Numbers
36th
Pangram Grep
43rd
Pernicious Numbers
48th
Prime Numbers
39th
Quine
1st
Recamán
34th
Rule 110
22nd
Seven Segment
38th
Spelling Numbers
22nd
Tongue-twisters
22nd
United States
32nd
Vampire Numbers
36th
Van Eck Sequence
22nd
π
45th261st82nd25th466th63rd13th
τ
26th126th
8th
φ
26th
8th
√2
33rd
9th
𝑒
34th
7th