Higher product bound for an approximate group (source code)

= Higher product bound for an approximate group

If $A$ is a finite $K$-<approximate group>, then
$$
A^m\subseteq X^{m-1}A,\qquad |A^m|\leq K^{m-1}|A|
$$
for every <positive integer> $m$, where $A^2\subseteq XA$ and $|X|\leq K$. This follows immediately by <mathematical induction>.