Abundant Numbers
791
Arithmetic Numbers
793
Card Number Validation
574
Catalan Numbers
664
Christmas Trees
721
Collatz
845
CSS Colors
123
Day of Week
896
Emirp Numbers
439
Emirp Numbers (Long)
527
Evil Numbers
642
Fizz Buzz
989
Leap Years
892
Niven Numbers
659
Pangram Grep
683
Prime Numbers
648
Tongue-twisters
341