On the Davenport constant and on the structure of extremal zero-sum free sequences
نویسندگان
چکیده
Let G = Cn1 ⊕ . . .⊕Cnr with 1 < n1 | . . . |nr be a finite abelian group, d∗(G) = n1 + . . .+ nr−r, and let d(G) denote the maximal length of a zero-sum free sequence over G. Then d(G) ≥ d∗(G), and the standing conjecture is that equality holds for G = Cr n. We show that equality does not hold for C2 ⊕ Cr 2n, where n ≥ 3 is odd and r ≥ 4. This gives new information on the structure of extremal zero-sum free sequences over Cr 2n.
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ورودعنوان ژورنال:
- Periodica Mathematica Hungarica
دوره 64 شماره
صفحات -
تاریخ انتشار 2012