MNOP rationality conjecture for reduced Donaldson–Thomas series

Let $X$) be a Calabi–Yau $3$-fold, let $\beta$ be a nonzero effective curve class, and let $\mathop{\rm DT}\nolimits'_{\beta}(X)$ denote the coefficient of $t^\beta$ in the reduced Donaldson–Thomas series. MNOP rationality conjecture. The Laurent series $\mathop{\rm DT}\nolimits'_{\beta}(X)$ is the Laurent expansion of a rational function of $q$ invariant under $q\leftrightarrow 1/q$. This asserts that the a priori formal Laurent series extends to a rational, hence meromorphic, function on the $q$-plane.