Christmas Trees
4th
Evil Numbers
49th
Fibonacci
50th
Happy Numbers
36th
Happy Numbers (Long)
37th
Intersection
20th
ISBN
32nd
Levenshtein Distance
11th
Look and Say
22nd
Lucky Tickets
17th
Niven Numbers
39th
Number Spiral
24th
Odious Numbers
54th
Pernicious Numbers
41st
Prime Numbers
56th
Prime Numbers (Long)
55th
Rule 110
15th
Tongue-twisters
Van Eck Sequence
23rd