Arithmetic Numbers
6th
Card Number Validation
5th
Collatz
11th
Divisors
26th
Evil Numbers
1st
Evil Numbers (Long)
1st
Leap Years
13th
Leyland Numbers
17th
Look and Say
8th
Niven Numbers
25th
Niven Numbers (Long)
23rd
Odious Numbers
1st
Odious Numbers (Long)
1st
Pernicious Numbers
26th
Pernicious Numbers (Long)
16th
Prime Numbers
1st
1st
Prime Numbers (Long)
1st
Smith Numbers
9th
United States
3rd
π
75th