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arXiv · 2209.14779

On the Number of Weighted Zero-sum Subsequences

A. Lemos·B. K. Moriya·A. O. Moura·A. T. Silva
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Abstract

Let $G$ be a finite additive abelian group with exponent $d^kn, d,n>1,$ and $k$ a positive integer. For $S$ a sequence over $G$ and $A=\{1,2,\ldots,d^kn-1\}\setminus\{d^kn/d^i:i\in[1,k]\}, $ we investigate the lower bound of the number $N_{A,0}(S)$, which denotes the number of $A$-weighted zero-sum subsequences of $S.$ In particular, we prove that $N_{A,0}(S)\ge 2^{|S|-D_A(G)+1},$ where $D_A(G)$ is the $A$-weighted Davenport Constant. We also characterize the structures of the extremal sequences for which equality holds for some groups.

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A. Lemos, B. K. Moriya, A. O. Moura, A. T. Silva. 2022-09-29. On the Number of Weighted Zero-sum Subsequences. https://arxiv.org/abs/2209.14779

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