Category:Definitions/Divisor Sum Function

This category contains definitions related to Divisor Sum Function.
Related results can be found in Category:Divisor Sum Function.

Let $n$ be an integer such that $n \ge 1$.

The divisor sum function $\map {\sigma_1} n$ is defined on $n$ as being the sum of all the positive integer divisors of $n$.

That is:

$\ds \map {\sigma_1} n = \sum_{d \mathop \divides n} d$

where $\ds \sum_{d \mathop \divides n}$ is the sum over all divisors of $n$.