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Number of ideals in an algebra

Let $R_{n,m}^q$ be the finite dimensional algebra $K<x_1,...,x_n>/J^m$, where the field $K$ has $q$ elements and $K<x_1,...,x_n>$ is the non-commutative polynomial ring with the ideal $J$ generated by $x_1,...,x_n$.

Let $T_{n,m}^q$ be the finite dimensional algebra $K[x_1,...,x_n]/J^m$, where the field $K$ has $q$ elements and $K[x_1,...,x_n]$ is the commutative polynomial ring with the ideal $J$ generated by $x_1,...,x_n$.

Question: What are the number of non-zero ideals of $R_{n,m}^q$ and $T_{n,m}^q$ for $n,m \geq 2$?

$R_{n,m}^q$ is commutative exactly when $m=2$ (and then coincides with $T_{n,m}^q$) and in this case the number of non-zero ideals seems to be given by the sequence $a_t^q=\sum\limits_{k=0}^{t}{[n,k]_q}$, where $[n,k]_q$ is the Gaussian binomial coefficient.

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