Let κ be an infinite cardinal. The sequential fan S_κ with κ-many spines is the quotient space obtained from the disjoint union of κ-many convergent se- quences by identifying all the limit points to a single point denoted by ∞. To be precise, S_κ={∞}∪(κ*ω) as a set, every point of κ*ω is isolated, and a basic neighborhood of ∞ is of the form U_ψ={∞}∪<α, n>: n≥ψ(α)} where ψ∈ω~κ.
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