Abundant Numbers
1st
Abundant Numbers (Long)
1st
Arithmetic Numbers
3rd
Ascending Primes
4th
Divisors
1st
Emirp Numbers
3rd
Emirp Numbers (Long)
1st
Evil Numbers
1st
Evil Numbers (Long)
1st
Factorial Factorisation
4th
Fibonacci
1st
Happy Numbers
1st
Happy Numbers (Long)
1st
ISBN
4th
Leap Years
14th
Look and Say
1st
Niven Numbers
1st
Niven Numbers (Long)
1st
Odious Numbers
1st
Odious Numbers (Long)
1st
Ordinal Numbers
4th
Pascalβs Triangle
1st
Pernicious Numbers
1st
Pernicious Numbers (Long)
5th
Prime Numbers
1st
Prime Numbers (Long)
1st
Quine
1st