Abundant Numbers
42nd
146th
Abundant Numbers (Long)
19th11th52nd69th83rd3rd
Collatz
44th
Divisors
13th48th88th126th5th
Evil Numbers
525th
Fibonacci
1st1st80th1st
10th
Leap Years
69th
313th
Niven Numbers (Long)
1st
Pangram Grep
41st
Prime Numbers
16th
Prime Numbers (Long)
16th
Roman to Arabic
18th
85th