12 Days of Christmas
Abundant Numbers
1,507th2,207th
Abundant Numbers (Long)
1,227th1,364th
Arithmetic Numbers
Catalan Numbers
Christmas Trees
Collatz
Divisors
Emirp Numbers
Emirp Numbers (Long)
Evil Numbers
Evil Numbers (Long)
Fibonacci
Fizz Buzz
Foo Fizz Buzz Bar
1,773rd585th
Happy Numbers
Happy Numbers (Long)
Inventory Sequence
Kolakoski Constant
Kolakoski Sequence
Leap Years
Look and Say
Lucky Numbers
Niven Numbers
1,381st514th
Niven Numbers (Long)
Odious Numbers
Odious Numbers (Long)
Ordinal Numbers
Pangram Grep
Pascal’s Triangle
Pernicious Numbers
Pernicious Numbers (Long)
Prime Numbers
Prime Numbers (Long)
Recamán
Sierpiński Triangle
Tongue-twisters
1,048th1,035th
Van Eck Sequence