12 Days of Christmas
56th
Abundant Numbers
48th
Abundant Numbers (Long)
36th
Arithmetic Numbers
33rd
Christmas Trees
19th
Collatz
8th
Cubes
20th
Diamonds
26th
Fibonacci
216th1st
Fizz Buzz
119th
Foo Fizz Buzz Bar
18th
Fractions
28th
Happy Numbers
21st
Happy Numbers (Long)
15th
Hilbert Curve
6th
Leap Years
36th
ln 2
10th
Look and Say
28th
Lucky Numbers
16th
Mandelbrot
12th
Niven Numbers
53rd
Niven Numbers (Long)
29th
Pascal’s Triangle
33rd
Quine
109th
Tongue-twisters
24th
Tower of Hanoi
41st
Trinomial Triangle
8th
γ
8th
λ
16th
π
21st
τ
14th
φ
17th
√2
14th
𝑒
17th