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arXiv · 2609.37920

Congruences for the Andrews--Uncu partition function $\mathcal{EO}_u(n)$

Nayandeep Deka Baruah·Hirakjyoti Das·Manjil P. Saikia·Abhishek Sarma
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Abstract

In 2018, Andrews defined and studied the partition function $\mathcal{EO}(n)$, which counts the number of partitions of $n$ where each even part is less than each odd part. Thereafter, Uncu considered a different subset of such partitions, namely those partitions counted by $\mathcal{EO}(n)$ where there are no repeated even parts (we denote the number of such partitions by $\mathcal{EO}_u(n)$). In this paper, we prove several congruences modulo powers of $2$ for $\mathcal{EO}_u(n)$. We also prove some infinite families of congruences as well as a recurrence for the number of this class of partitions. Our methods involve elementary, algorithmic, and modular form techniques.

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Nayandeep Deka Baruah, Hirakjyoti Das, Manjil P. Saikia, Abhishek Sarma. 2026-09-29. Congruences for the Andrews--Uncu partition function $\mathcal{EO}_u(n)$. https://arxiv.org/abs/2609.37920

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