What does the set-builder notation with ∀n mean for membership?

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cappadonza
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Hi this is more of a set theory question really, I'm a bit confused,

say [tex]\mathcal{F}[/tex] is collections of sets, and [tex]\mathcal{F}_n[/tex] is a sequence of sub collections of sets and say [tex]B_{1}, B_{2} ...[/tex] is a sequence of sets
what does the following mean [tex]\mathcal{S} = \{ A \in \mathcal{F} \colon A \cap B_{n} \in \mathcal{F}_n \forall n \in \mathbb{N} \}[/tex]

for an element to be a member of the set [tex]\mathcal{S}[/tex] which of the conditons must be statisfy
does this mean if [tex]A \cap B_{1} \in \mathcal{F}_1 , \space A \cap B_{2} \in \mathcal{F}_2 ...[/tex] then it belongs to the set or
does it mean all these conditons must be met of it to be a members of the set [tex]A \cap B_{1} \in \mathcal{F}_1 , \space A \cap B_{1} \in \mathcal{F}_2 , \space A \cap B_{1} \in \mathcal{F}_3 ...[/tex] for each [tex]B_{1}, B_{2} ...[/tex]
 
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The first is the correct interpretation, if [itex]A \cap B_1\in\mathcal{F}_1[/itex] and [itex]A \cap B_2\in\mathcal{F}_2[/itex], etc., for all n = 1, 2,..., then A is in the collection.