12 Days of Christmas
80
Abundant Numbers
477
Arabic to Roman
361
Collatz
706
Divisors
770
Emirp Numbers
365
Evil Numbers
835
Evil Numbers (Long)
815
Fibonacci
934
Fizz Buzz
348
Foo Fizz Buzz Bar
516
Fractions
414
Happy Numbers
396
Happy Numbers (Long)
426
Leap Years
743
743
Niven Numbers
719
Niven Numbers (Long)
785
Odious Numbers
799
Odious Numbers (Long)
780
Pascal’s Triangle
799
Pernicious Numbers
349
Prime Numbers
688
Recamán
543
Smith Numbers
537
Van Eck Sequence
473
π
56
τ
56
φ
112
47
50