12 Days of Christmas
13th
Abundant Numbers
12th
Abundant Numbers (Long)
13th
Arithmetic Numbers
12th
Ascending Primes
10th
Catalan Numbers
14th
Catalan’s Constant
7th
Collatz
14th
Divisors
15th
Emirp Numbers
14th
Emirp Numbers (Long)
10th
Evil Numbers
11th61st
Evil Numbers (Long)
11th43rd
Factorial Factorisation
10th
Farey Sequence
17th
Fibonacci
26th
Fizz Buzz
27th291st2,333rd
Foo Fizz Buzz Bar
13th80th
Fractions
12th
Happy Numbers
22nd
Happy Numbers (Long)
14th
Leap Years
14th
Look and Say
13th
Medal Tally
8th
Niven Numbers
19th
Niven Numbers (Long)
12th
Odious Numbers
13th61st
Odious Numbers (Long)
11th40th
Pangram Grep
18th
Pernicious Numbers
15th
Pernicious Numbers (Long)
13th
Prime Numbers
15th
Prime Numbers (Long)
15th
Quine
16th
Recamán
8th
Time Distance
6th
Tongue-twisters
23rd
United States
7th
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