Abundant Numbers
46th
Christmas Trees
36th
Day of Week
Diamonds
15th
Divisors
1st
Emirp Numbers
11th
Fibonacci
1st
Fizz Buzz
13th
Leap Years
39th
ln 2
10th
Look and Say
20th
Ordinal Numbers
11th
Pangram Grep
23rd
Pascal’s Triangle
21st
Pernicious Numbers
41st
Prime Numbers
30th
Quine
1st
Recamán
11th