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arXiv · 2411.02978

Arithmetic properties of $5$-regular partitions into distinct parts

Nayandeep Deka Baruah·Abhishek Sarma
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Abstract

A partition is said to be $\ell$-regular if none of its parts is a multiple of $\ell$. Let $b^\prime_5(n)$ denote the number of 5-regular partitions into distinct parts (equivalently, into odd parts) of $n$. This function has also close connections to representation theory and combinatorics. In this paper, we study arithmetic properties of $b^\prime_5(n)$. We provide full characterization of the parity of $b^\prime_5(2n+1)$, present several congruences modulo 4, and prove that the generating function of the sequence $(b^\prime_5(5n+1))$ is lacunary modulo any arbitrary positive powers of 5.

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Nayandeep Deka Baruah, Abhishek Sarma. 2024-11-05. Arithmetic properties of $5$-regular partitions into distinct parts. https://arxiv.org/abs/2411.02978

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