Answer
$v = 2 c$
The relative velocity of recession greater than $c$
Work Step by Step
We can use the classical Doppler equation to find the relative recession speed:
$v = \frac{\lambda-\lambda_0}{\lambda_0}~c$
$v = \frac{3\lambda_0-\lambda_0}{\lambda_0}~c$
$v = \frac{2\lambda_0}{\lambda_0}~c$
$v = 2 c$
The relative velocity of recession is greater than $c$
