Let G be an additive abelian group of finite order n and let A be a non-empty set of integers. The Davenport constant of G with weight A, DA(G), is the smallest k ∈ Z+ such that for any sequence x1, . . . , xk of elements in G, there exists a nonempty subsequence xj1 ! , . . . , xjr and corresponding weights a1, . . . , ar ∈ A such that r i=1 aixji = 0. Similarly, EA(G) is the smallest positive integer k such that for any sequence x1, . . . , xk of elements in G there exists a non-empty subsequence of exactly n terms, xj1 , . . . , xjn ! , and corresponding weights a1, . . . , an ∈ A such that n i=1 aixji = 0. We consider these constants when G = Zn and A = {b2|b ∈ Z? n}, proving lower bounds for each.
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