Abundant Numbers
11th
Abundant Numbers (Long)
11th
Arithmetic Numbers
124th
Ascending Primes
23rd
Collatz
1,308th
Divisors
18th
Emirp Numbers
23rd
Emirp Numbers (Long)
1st
Evil Numbers
1st
Evil Numbers (Long)
1st
Factorial Factorisation
29th
Fibonacci
1st
Happy Numbers
1st
Happy Numbers (Long)
1st
ISBN
6th
Leap Years
1,817th
Look and Say
3rd
Lucky Numbers
320th
Niven Numbers
1st
Niven Numbers (Long)
1st
Odious Numbers
1st
Odious Numbers (Long)
1st
Ordinal Numbers
353rd
Pascalβs Triangle
1st
Pernicious Numbers
20th
Pernicious Numbers (Long)
75th
Prime Numbers
1st
Prime Numbers (Long)
1st
Quine
1st