Infinitely often and almost always

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Let A1,A2,A3, be a sequence of events in some sample space Ω.

In the following table, all statements in the "infinitely often" column are logically equivalent. Similarly, all statements in the "almost always" column are logically equivalent.

perspective infinitely often almost always
unions and intersections ωN=1n=NAn ωN=1n=NAn
first-order quantifiers N1nN:ωAn N1nN:ωAn
verbal expression ωAn for infinitely many n1 ωAn for almost all n1, i.e. ωAn for all but finitely many n1, i.e. ωAn for finitely many n1
lim sup/lim inf ωlim supnAn ωlim infnAn
limit of sup/inf ωlimNn=NAn ωlimNn=NAn