12 Days of Christmas
51st
99 Bottles of Beer
53rd
Abundant Numbers
60th
Arrows
43rd
CSS Colors
29th
Diamonds
167th
Divisors
88th
Emirp Numbers
16th
Evil Numbers
78th
142nd
Fibonacci
180th
193rd
Fizz Buzz
222nd
1st
217th
Happy Numbers
17th
55th
Leap Years
168th77th
37th
62nd105th
50th
330th
Leyland Numbers
20th
Lucky Tickets
23rd
Morse Decoder
53rd
Morse Encoder
46th
Niven Numbers
1st
154th
Odious Numbers
76th
313th
Ordinal Numbers
71st
Pangram Grep
Pascal’s Triangle
66th
Pernicious Numbers
64th
171st
Prime Numbers
1st
358th
Quine
1st25th102nd1st84th26th63rd123rd5th70th33rd1st1st47th122nd49th37th79th44th100th
Rule 110
61st
Seven Segment
84th
Spelling Numbers
19th
United States
λ
50th
27th
39th47th41st155th16th
π
53rd
τ
50th
φ
74th
√2
86th
𝑒
87th