12 Days of Christmas
24th
99 Bottles of Beer
33rd
Abundant Numbers
17th
Arabic to Roman
24th
Christmas Trees
10th
Divisors
19th
Emirp Numbers
21st
Evil Numbers
51st
Fibonacci
1st
Fizz Buzz
43rd
Foo Fizz Buzz Bar
16th
Happy Numbers
50th
Leap Years
22nd
Niven Numbers
31st
Odious Numbers
48th
Ordinal Numbers
19th
Pangram Grep
9th
Pascal’s Triangle
33rd
Pernicious Numbers
38th
Prime Numbers
42nd
Roman to Arabic
13th
Seven Segment
17th
Spelling Numbers
United States
23rd
λ
13th
π
26th
τ
19th
φ
32nd
√2
38th
𝑒
25th