The MacMahon $q$-Catalan is convex
  Let $n\geq2$ be an integer. In this paper, we study the convexity of the so-called MacMahon's $q$-Catalan polynomials $C_n(q)=\frac1{[n+1]_q}\left[ 2n \atop n \right]_q$ as functions of $q$. Along the way, several intermediate results on inequalities are presented including a commentary on the convexity of the generation function for the integer partitions. 
Tewodros Amdeberhan
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