On the distribution of $t$-hooks of doubled distinct partitions
Hyunsoo Cho, Byungchan Kim, Eunmi Kim, Ae Ja Yee
TL;DR
The paper studies the distribution of $t$-hooks in doubled distinct partitions and of $t$-shifted hooks in strict partitions by deriving explicit generating functions via the Littlewood decomposition. Using a circle-method framework, it proves that both $N_{t,2n}^{\mathcal{DD}}$ and $\widehat{N}_{t,2n}^{\mathcal{DD}}$ are asymptotically normal, and it provides detailed asymptotic formulas for their means and variances. The results extend prior work on hook-length distributions from all partitions and self-conjugate partitions to these two structured families, linking combinatorial decompositions with analytic techniques such as the dilogarithm and Wright’s circle method. The generating functions $F_t(x;q)$ and $\widehat{F}_t(x;q)$ encode the joint structure of $t$-cores and $t$-quotients, enabling precise asymptotics and moment calculations. Overall, the work sheds light on universal normality phenomena in partition hook-length statistics and broadens the landscape of partition-analytic methods in representation-theoretic contexts.
Abstract
Recently, Griffin, Ono, and Tsai examined the distribution of the number of $t$-hooks in partitions of $n$, which was later followed by the work of Craig, Ono, and Singh on the distribution of the number of $t$-hooks in self-conjugate partitions of $n$. Motivated by these studies, in this paper, we further investigate the number of $t$-hooks in some subsets of partitions. More specifically, we obtain the generating functions for the number of $t$-hooks in doubled distinct partitions and the number of $t$-shifted hooks in strict partitions. Based on these generating functions, we prove that the number of $t$-hooks in doubled distinct partitions and the number of $t$-shifted hooks in strict partitions are both asymptotically normally distributed.
