Abundant Numbers
83rd
Abundant Numbers (Long)
3rd
Arithmetic Numbers
79th
Ascending Primes
21st
Collatz
1,056th
Divisors
18th
Emirp Numbers
34th
Emirp Numbers (Long)
1st
Evil Numbers
1st
Evil Numbers (Long)
1st
Factorial Factorisation
32nd
Fibonacci
1st
Happy Numbers
298th
Happy Numbers (Long)
2nd
ISBN
15th
Leap Years
2,214th
Look and Say
3rd
Lucky Numbers
319th
Niven Numbers
459th
Niven Numbers (Long)
2nd
Odious Numbers
1st
Odious Numbers (Long)
1st
Ordinal Numbers
383rd
Pascal’s Triangle
1st
Pernicious Numbers
21st
Pernicious Numbers (Long)
73rd
Prime Numbers
1st
Prime Numbers (Long)
1st
Quine
1st