12 Days of Christmas
123rd
Abundant Numbers
383rd
Christmas Trees
137th
Diamonds
170th
Divisors
108th
Emirp Numbers
260th
Evil Numbers
466th
Fibonacci
166th
Fizz Buzz
707th
Happy Numbers
545th
Leap Years
417th
Leyland Numbers
316th
Morse Decoder
114th
Morse Encoder
113th
Niven Numbers
66th
Odious Numbers
276th
Ordinal Numbers
200th
Pangram Grep
109th
Pascal’s Triangle
41st
Pernicious Numbers
263rd
Prime Numbers
480th
Recamán
190th
Rock-paper-scissors-Spock-lizard
98th
Seven Segment
168th
Sierpiński Triangle
77th
φ
145th
√2
353rd
𝑒
237th