Relation between Signed and Unsigned Stirling Numbers of the First Kind

Theorem
Let $m, n \in \Z_{\ge 0}$ be positive integers.

Then:
 * $\displaystyle {n \brack m} = \paren {-1}^{n + m} \map s {n, m}$

where:
 * $\displaystyle {n \brack m}$ denotes an unsigned Stirling number of the first kind
 * $\map s {n, m}$ denotes a signed Stirling number of the first kind.