Simplifying group actions
نویسندگان
چکیده
منابع مشابه
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Let K be any field, K(x1, . . . , xn) be the rational function field of n variables over K, and Sn and An be the symmetric group and the alternating group of degree n respectively. For any a ∈ K \ {0}, define an action of Sn on K(x1, . . . , xn) by σ · xi = xσ(i) for σ ∈ An and σ · xi = a/xσ(i) for σ ∈ Sn \ An. Theorem. For any field K and n = 3, 4, 5, the fixed field K(x1, . . . , xn) Sn is ra...
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ژورنال
عنوان ژورنال: Topology and its Applications
سال: 1997
ISSN: 0166-8641
DOI: 10.1016/s0166-8641(96)00084-3