Cohen–Lenstra Heuristics of Quadratic Number Fields

  • Étienne Fouvry
  • Jürgen Klüners
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4076)


We establish a link between some heuristic asymptotic formulas (due to Cohen and Lenstra) concerning the moments of the p–part of the class groups of quadratic fields and formulas giving the frequency of the values of the p–rank of these class groups.

Furthermore we report on new results for 4–ranks of class groups of quadratic number fields.


Abelian Group Limit Point Class Group Vector Subspace Quadratic Number 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Étienne Fouvry
    • 1
  • Jürgen Klüners
    • 2
  1. 1.Mathématique, Bât. 425Univ. Paris–SudORSAYFrance
  2. 2.Fachbereich Mathematik/InformatikUniversität KasselKasselGermany

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