On the Largest Part Size and Its Multiplicity of a Random Integer Partition

Abstract

Let $\lambda$ be a partition of the positive integer $n$ chosen umiformly at random among all such partitions. Let $L_n=L_n(\lambda )$ and $M_n=M_n(\lambda )$ be the largest part size and its multiplicity, respectively. For large $n$, we focus on a comparison between the partition statistics $L_n$ and $L_n{M}_n$. In terms of convergence in distribution, we show that they behave in the same way. However, it turns out that the expectation of $L_n{M}_n-L_n$ grows as fast as $\frac{1}{2}\log n$ We obtain a precise asymptotic expansion for this expectation and conclude with an open problem arising from this study.

14 pages, 1 figure