12 Days of Christmas
173
Abundant Numbers
497
Arabic to Roman
505
Collatz
842
Divisors
813
Emirp Numbers
450
Evil Numbers
835
Evil Numbers (Long)
815
Fibonacci
934
Fizz Buzz
382
Foo Fizz Buzz Bar
649
Fractions
487
Happy Numbers
510
Happy Numbers (Long)
502
Leap Years
744
743
Niven Numbers
721
Niven Numbers (Long)
787
Odious Numbers
799
Odious Numbers (Long)
780
Pascal’s Triangle
862
Pernicious Numbers
349
Prime Numbers
688
Recamán
602
Smith Numbers
730
Van Eck Sequence
500
π
63
τ
62
φ
113
47
51