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arXiv · 2111.12031

Partitions Associated to Class Groups of Imaginary Quadratic Number Fields

Kathleen Petersen·James Sellers
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Abstract

We investigate properties of attainable partitions of integers, where a partition $(n_1,n_2, \dots, n_r)$ of $n$ is attainable if $\sum (3-2i)n_i\geq 0$. Conjecturally, under an extension of the Cohen and Lenstra heuristics by Holmin et. al., these partitions correspond to abelian $p$-groups that appear as class groups of imaginary quadratic number fields for infinitely many odd primes $p$. We demonstrate a connection to partitions of integers into triangular numbers, construct a generating function for attainable partitions, and determine the maximal length of attainable partitions.

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Kathleen Petersen, James Sellers. 2021-11-23. Partitions Associated to Class Groups of Imaginary Quadratic Number Fields. https://arxiv.org/abs/2111.12031

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