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Asymmetric decompositions of Abelian groups - MaRDI portal

Asymmetric decompositions of Abelian groups (Q1972538)

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scientific article; zbMATH DE number 1429644
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Asymmetric decompositions of Abelian groups
scientific article; zbMATH DE number 1429644

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    Asymmetric decompositions of Abelian groups (English)
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    3 August 2000
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    A subset \(A\) of an Abelian group \(G\) is said to be asymmetric if \(g+S\not\subset A\) for any element \(g\in G\) and any infinite symmetric subset \(S\subset G\) (\(S=-S\)). The minimal cardinality of a decomposition of the group \(G\) into asymmetric sets is denoted by \(\nu(G)\). For any Abelian group \(G\), the cardinal number \(\nu(G)\) is expressed via the following cardinal invariants: the free rank, the 2-rank, and the cardinality of the group. In particular, \(\nu(\mathbb{Z}^n)=n+1\), \(\nu(\mathbb{Q}^n)=n+2\), and \(\nu(\mathbb{R})=\aleph_0\).
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    asymmetric decompositions
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    Abelian groups
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    symmetric sets
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    cardinal invariants
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    free rank
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