12 Days of Christmas
381st
Christmas Trees
544th
Diamonds
381st
Divisors
306th1st
Emirp Numbers
146th
Evil Numbers
346th355th
Fibonacci
168th173rd
Fizz Buzz
1,097th853rd
Happy Numbers
281st
Leap Years
270th445th
Niven Numbers
143rd198th
Odious Numbers
282nd242nd
Pangram Grep
283rd
Pascal’s Triangle
53rd
Pernicious Numbers
404th
Prime Numbers
80th
313th
Quine
30th67th
Sudoku
π
212th
τ
160th
φ
168th