IMAGINARY QUADRATIC FIELDS WITH Cl2(k) ≃ (2, 2, 2)
نویسنده
چکیده
We characterize those imaginary quadratic number fields, k, with 2-class group of type (2, 2, 2) and with the 2-rank of the class group of its Hilbert 2-class field equal to 2. We then compute the length of the 2-class field tower of k.
منابع مشابه
Imaginary Quadratic
is called the 2-class field tower of k. If n is the minimal integer such that kn = kn+1, then n is called the length of the tower. If no such n exists, then the tower is said to be of infinite length. At present there is no known decision procedure to determine whether or not the (2-)class field tower of a given field k is infinite. However, it is known by group theoretic results (see [2]) that...
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