Given $Q_{n+1}$ what is $Q_n$

Question

Given :

$$ Q_{n+1}=Q_n+\frac{1}{n}[R_n - Q_n] $$

I'm attempting to understand the value of $Q_n$

Is the following correct ? :

$$ Q_{n}=Q_{n-1}+\frac{1}{n-1}[R_{n-1} - Q_{n-1}] $$