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Identities for field extensions generalizing the Ohno–Nakagawa relations

Published online by Cambridge University Press:  30 June 2015

Henri Cohen
Affiliation:
Université de Bordeaux, Institut de Mathématiques, UMR 5251 du CNRS, 351 Cours de la Libération, 33405 Talence Cedex, France email Henri.Cohen@math.u-bordeaux1.fr
Simon Rubinstein-Salzedo
Affiliation:
Department of Statistics, Stanford University, 390 Serra Mall, Stanford, CA 94305, USA email simonr@stanford.edu
Frank Thorne
Affiliation:
Department of Mathematics, University of South Carolina, 1523 Greene Street, Columbia, SC 29208, USA email thorne@math.sc.edu
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Abstract

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In previous work, Ohno conjectured, and Nakagawa proved, relations between the counting functions of certain cubic fields. These relations may be viewed as complements to the Scholz reflection principle, and Ohno and Nakagawa deduced them as consequences of ‘extra functional equations’ involving the Shintani zeta functions associated to the prehomogeneous vector space of binary cubic forms. In the present paper, we generalize their result by proving a similar identity relating certain degree-$\ell$ fields to Galois groups $D_{\ell }$ and $F_{\ell }$, respectively, for any odd prime $\ell$; in particular, we give another proof of the Ohno–Nakagawa relation without appealing to binary cubic forms.

Type
Research Article
Copyright
© The Authors 2015 

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