Let A₁,A₂,dots be sets such that for each n we have ⋂[infinity]ₙᵢ₌₁ Aᵢ ≠ ∅ . Is it possible for ⋂[infinity]ₙᵢ₌₁ Aᵢ ≠ ∅? (In order to receive credit you must either demonstrate an example that shows that it is possible that ⋂[infinity]ₙᵢ₌₁ Aᵢ = ∅ , or prove that there cannot exist such sets.)
