Proof of a nonnegativity conjecture of Prellberg--Stanton

Hong-Zhang Ai, Lili Mu, Bao-Xuan Zhu

In 1994, Friedman, Joichi and Stanton conjectured that coefficients of the power-series $q+(1-q){\prod }_{i=n}^{2n-1}\frac{1}{1-q^i}$ are nonnegative for $n\ge 3$ and $n$ being odd.…