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[parent] push-down theorem on class numbers (Theorem)

As in the parent entry, given a number field $K$ , the class number of $K$ is denoted by $h_K$ .

Theorem 1 (Pushing-Down Theorem)   Let $E/F$ be a $p$ -extension of number fields and suppose that only one prime ideal of $F$ is ramified in $E$ and that this prime is totally ramified. Then $p|h_E$ implies $p|h_F$ .

Bibliography

Fröh
A. Fröhlich, On a method for the determination of class number factors in number fields, Mathematika, 4 (1957), 113-121.
Iwas
K. Iwasawa, A note on Class Numbers of Algebraic Number Fields, Abh. Math. Sem. Univ. Hamburg, 20 (1956), 257-258.




"push-down theorem on class numbers" is owned by alozano.
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See Also: ideal class, $p$-extension, extensions without unramified subextensions and class number divisibility, class number divisibility in $p$-extensions, topics on ideal class groups and discriminants


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Cross-references: implies, totally ramified, prime, ramified, prime ideal, theorem, class number, number field
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This is version 3 of push-down theorem on class numbers, born on 2005-02-23, modified 2005-02-23.
Object id is 6815, canonical name is PushDownTheoremOnClassNumbers.
Accessed 1482 times total.

Classification:
AMS MSC11R29 (Number theory :: Algebraic number theory: global fields :: Class numbers, class groups, discriminants)
 11R32 (Number theory :: Algebraic number theory: global fields :: Galois theory)
 11R37 (Number theory :: Algebraic number theory: global fields :: Class field theory)

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