Kaffeleif

12 Days of Christmas

Abundant Numbers

Abundant Numbers (Long)

Arithmetic Numbers

Ascending Primes

Catalan Numbers

Catalan’s Constant

Collatz

Divisors

Emirp Numbers

Emirp Numbers (Long)

Evil Numbers

Evil Numbers (Long)

Factorial Factorisation

Farey Sequence

Fibonacci

Fizz Buzz

Foo Fizz Buzz Bar

Fractions

Happy Numbers

Happy Numbers (Long)

Leap Years

Look and Say

Medal Tally

Niven Numbers

Niven Numbers (Long)

Odious Numbers

Odious Numbers (Long)

Pangram Grep

Pernicious Numbers

Pernicious Numbers (Long)

Prime Numbers

Prime Numbers (Long)

Quine

Recamán

Time Distance

Tongue-twisters

United States

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