12 Days of Christmas
576th
Abundant Numbers
220th
Arabic to Roman
252nd
Christmas Trees
235th
Cubes
268th
Diamonds
162nd
Divisors
1st
Emirp Numbers
292nd
Evil Numbers
58th1st
Fibonacci
189th172nd
Fizz Buzz
66th
Happy Numbers
225th
Leap Years
228th
Morse Decoder
79th
Morse Encoder
94th
Niven Numbers
63rd51st
Odious Numbers
57th1st
Ordinal Numbers
7th
Pangram Grep
421st
Pascal’s Triangle
83rd
Pernicious Numbers
414th
Prime Numbers
269th
Quine
82nd
Rock-paper-scissors-Spock-lizard
134th
Roman to Arabic
290th
Rule 110
250th
Seven Segment
96th
Sierpiński Triangle
83rd
Spelling Numbers
199th
United States
138th
φ
181st
√2
241st