12 Days of Christmas
51st
99 Bottles of Beer
38th
Abundant Numbers
69th
Arabic to Roman
29th
Christmas Trees
77th
CSS Colors
38th
Cubes
18th
Diamonds
22nd
Divisors
34th
Emirp Numbers
49th
Evil Numbers
98th
Fibonacci
1st
Fizz Buzz
67th
Happy Numbers
43rd
Kolakoski Sequence
29th
Leap Years
49th
Look and Say
34th
Niven Numbers
57th
Odious Numbers
75th
Ordinal Numbers
40th
Pangram Grep
49th
Pernicious Numbers
56th
Prime Numbers
45th
Quine
1st
Recamán
40th
Rule 110
22nd
Seven Segment
44th
Spelling Numbers
27th
Tongue-twisters
26th
United States
37th
Vampire Numbers
40th
Van Eck Sequence
26th
π
51st289th91st27th515th66th10th
τ
31st137th
9th
φ
31st
10th
√2
39th
10th
𝑒
40th
9th