Tau - the number of divisors of n
Rule
Each term is: The number of the number's divisors
Known as: Tau - the number of divisors of n
The number of divisors of n.
Tau is even when n is not a perfect square, because the divisors then occur in pairs.
The first 50 terms (starting from n=1) are:
1 2 2 3 2 4 2 4 3 4 2 6 2 4 4 5 2 6 2 6 4 4 2 8 3 4 4 6 2 8 2 6 4 4 4 9 2 4 4 8 2 8 2 6 6 4 2 10 3 6
Example
To get the value for n=15:
- Find the number's divisors, giving 1, 3, 5, 15
- Count them, giving 4.
So the result is 4.