Let G be an additive finite abelian group. For a sequence T over G and g∈G\documentclass[12pt]{minimal}
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\begin{document}$$g\in G$$\end{document}, let vg(T)\documentclass[12pt]{minimal}
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\begin{document}$$\mathrm {v}_{g}(T)$$\end{document} denote the multiplicity of g in T. Let B(G)\documentclass[12pt]{minimal}
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\begin{document}$$\mathcal {B}(G)$$\end{document} denote the set of all zero-sum sequences over G. For Ω⊂B(G)\documentclass[12pt]{minimal}
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\begin{document}$$\Omega \subset \mathcal {B}(G)$$\end{document}, let dΩ(G)\documentclass[12pt]{minimal}
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\begin{document}$$\mathsf {d}_{\Omega }(G)$$\end{document} be the smallest integer t such that every sequence S over G of length |S|≥t\documentclass[12pt]{minimal}
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\begin{document}$$|S|\ge t$$\end{document} has a subsequence in Ω\documentclass[12pt]{minimal}
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\begin{document}$$\Omega $$\end{document}. The invariant dΩ(G)\documentclass[12pt]{minimal}
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\begin{document}$$\mathsf {d}_{\Omega }(G)$$\end{document} was formulated recently in [3] to take a unified look at zero-sum invariants, it led to the first results there, and some open problems were formulated as well. In this paper, we make some further study on dΩ(G)\documentclass[12pt]{minimal}
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\begin{document}$$\mathsf {d}_{\Omega }(G)$$\end{document}. Let q′(G)\documentclass[12pt]{minimal}
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\begin{document}$${\mathsf {q}}'(G)$$\end{document} be the smallest integer t such that every sequence S over G of length |S|≥t\documentclass[12pt]{minimal}
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\begin{document}$$|S|\ge t$$\end{document} has two nonempty zero-sum subsequences, say T1\documentclass[12pt]{minimal}
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\begin{document}$$T_{1}$$\end{document} and T2\documentclass[12pt]{minimal}
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\begin{document}$$T_{2}$$\end{document}, having different forms, i.e., vg(T1)≠vg(T2)\documentclass[12pt]{minimal}
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\begin{document}$$\mathrm {v}_{g}(T_{1})\ne \mathrm {v}_{g}(T_{2})$$\end{document} for some g∈G\documentclass[12pt]{minimal}
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\begin{document}$$g\in G$$\end{document}. Let q(G)\documentclass[12pt]{minimal}
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\begin{document}$${\mathsf {q}}(G)$$\end{document} be the smallest integer t such that ⋂dΩ(G)=tΩ=∅.\documentclass[12pt]{minimal}
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\begin{document}$$\begin{aligned} \bigcap _{{\mathsf {d}}_{\Omega }(G)=t}\Omega =\emptyset . \end{aligned}$$\end{document}The invariants q(G)\documentclass[12pt]{minimal}
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\begin{document}$${\mathsf {q}}(G)$$\end{document} and q′(G)\documentclass[12pt]{minimal}
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\begin{document}$${\mathsf {q}}'(G)$$\end{document} were also introduced in [3]. We prove, among other results, that q(G)=q′(G)\documentclass[12pt]{minimal}
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\begin{document}$${\mathsf {q}}(G)={\mathsf {q}}'(G)$$\end{document} in fact.
