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Some Finite Abelian Group Theory and Some \({q}\)-Series Identities

Abstract

The purpose of this article is to compute certain weighted sums over various subposets of the poset of isomorphism classes of finite abelian \({\ell}\)-groups, where \({\ell}\) is a fixed odd prime. These sums are similar to previous sums computed by Hall and Cohen-Lenstra. The computation expands upon the previous analysis of Cohen-Lenstra while also using the tools of hypergeometric functions and \({q}\)-series. The identities computed in this article, while aesthetically pleasing in their own right, also turn out to be applicable to the construction of a random matrix version of the Cohen-Lenstra-Martinet heuristics.

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Correspondence to Derek Garton.

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Garton, D. Some Finite Abelian Group Theory and Some \({q}\)-Series Identities. Ann. Comb. 20, 361–371 (2016). https://doi.org/10.1007/s00026-016-0299-8

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  • DOI: https://doi.org/10.1007/s00026-016-0299-8

Mathematics Subject Classification

  • 05E15
  • 20K01

Keywords

  • posets
  • finite abelian groups
  • \({q}\)-series