12 Days of Christmas
36th
24 Game
10th
99 Bottles of Beer
22nd
Arrows
20th
Card Number Validation
14th
Collatz
30th
Day of Week
25th
Diamonds
27th
Divisors
128th
Farey Sequence
18th
Fizz Buzz
251st
Forsyth–Edwards Notation
11th
ISBN
18th
Kaprekar Numbers
9th
Leap Years
72nd
Niven Numbers
57th
Pernicious Numbers
44th
Rock-paper-scissors-Spock-lizard
9th
Seven Segment
29th
Ten-pin Bowling
8th
Tongue-twisters
21st
π
14th
𝑒
17th