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NONABELIAN NORMAL CM-FIELDS OF DEGREE 2pq

Published online by Cambridge University Press:  01 August 2009

S.-H. KWON
Affiliation:
Department of Mathematics Education, Korea University, 136-701, Seoul, Korea (email: [email protected])
S. LOUBOUTIN*
Affiliation:
Institut de Mathématiques de Luminy, UMR 6206, 163 avenue de Luminy, Case 907, 13288 Marseille Cedex 9, France (email: [email protected])
S.-M. PARK
Affiliation:
Department of Mathematics, Korea University, 136-701, Seoul, Korea (email: [email protected])
*
For correspondence; e-mail: [email protected]
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Abstract

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We prove that the relative class number of a nonabelian normal CM-field of degree 2pq (where p and q are two distinct odd primes) is always greater than four. Not only does this result solve the class number one problem for the nonabelian normal CM-fields of degree 42, but it has also been used elsewhere to solve the class number one problem for the nonabelian normal CM-fields of degree 84.

Type
Research Article
Copyright
Copyright © Australian Mathematical Publishing Association Inc. 2009

Footnotes

The research of the first author was supported by a Korea University Grant.

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