Definition:Stirling Numbers of the First Kind/Notation

Definition
The notation $\displaystyle \left[{n \atop k}\right]$ for the unsigned Stirling numbers of the first kind is that proposed by and publicised by.

The notation $s \left({n, k}\right)$ for the signed Stirling numbers of the first kind is similar to variants of that sometimes given for the unsigned.

Usage is inconsistent in the literature.