Published online by Cambridge University Press: 20 November 2018
We investigate the problem of determining when $\text{IA}({{F}_{n}}({{\mathbf{A}}_{m}}\mathbf{A}))$ is finitely generated for all
$n$ and
$m$, with
$n\ge 2$ and
$m\ne 1$. If
$m$ is a nonsquare free integer then
$\text{IA}({{F}_{n}}({{\mathbf{A}}_{m}}\mathbf{A}))$ is not finitely generated for all
$n$ and if
$m$ square free integer then
$\text{IA}({{F}_{n}}({{\mathbf{A}}_{m}}\mathbf{A}))$ is finitely generated for all
$n$, with
$n\ne 3$, and
$\text{IA}({{F}_{3}}({{\mathbf{A}}_{m}}\mathbf{A}))$ is not finitely generated. In case
$m$ is square free, Bachmuth and Mochizuki claimed in ([7], Problem 4) that
$\text{TR}({{\mathbf{A}}_{m}}\mathbf{A})$ is 1 or 4. We correct their assertion by proving that
$\text{TR}({{\mathbf{A}}_{m}}\mathbf{A})=\infty$.