Symbols:Greek/Sigma/Divisor Function

Divisor Function

$\map {\sigma_\alpha} n$

Let $\alpha \in \Z_{\ge 0}$ be a non-negative integer.

A divisor function is an arithmetic function of the form:

$\ds \map {\sigma_\alpha} n = \sum_{m \mathop \divides n} m^\alpha$

where the summation is taken over all $m \le n$ such that $m$ divides $n$).

The $\LaTeX$ code for \(\map {\sigma_\alpha} n\) is \map {\sigma_\alpha} n .

Sources

• 1989: Ephraim J. Borowski and Jonathan M. Borwein: Dictionary of Mathematics ... (previous) ... (next): sigma function or $\sigma$ function: 2.