More concretely, let $I$ be a monimial ideal in $\mathbb{C}[x_1,\ldots,x_n]$ such that the ring $A=\mathbb{C}[x_1,\ldots,x_n]/I$ is one dimensional. Let $X=\operatorname{Spec}A$, and let $X^{[n]}$ be the punctual Hilbert scheme of points located at the origin. Then is it true that the generating series for Euler characteristic $\sum_{n}\chi(X^{[n]})t^n$ is rational?
