I was wondering if for an arbitrary valuation ring $R$ and an element $\pi$ in the maximal ideal of $R$, the rings
$R[x_1,\ldots,x_n]$;
projective limit of $R/(\pi^l)[x_1,\ldots,x_n]$, probably also denoted as $R \langle x_1,\ldots,x_n \rangle$ in the case when $R$ is a rank 1 valuation ring and;
$R/(\pi)[x_1,\ldots,x_n]$
are coherent or not?
The obvious implication being that either (1) or (2) would imply (3), and I think in the rank 1 valuation case all three rings considered above are indeed coherent. But I really don't know anything about this question in general. Any comment would be helpful.