query: Countable union of disjoint finite sets is countable
positive_passages.docid: 149673
positive_passages.text: Cardinality of an infinite union of finite sets
negative_passages.docid: 27937
negative_passages.text: Cartesian Product of Two Countable Sets is Countable
negative_passages.docid: 44974
negative_passages.text: Infinite set and countable subsets
negative_passages.docid: 130361
negative_passages.text: Basis for a topology with a countable number of sets
negative_passages.docid: 23442
negative_passages.text: Cardinality of the union of infinite and countable sets
negative_passages.docid: 44623
negative_passages.text: Closed set as a countable intersection of open sets
negative_passages.docid: 128437
negative_passages.text: How to prove that a finite set is countable
negative_passages.docid: 23907
negative_passages.text: $Seq (\mathbb{N})$ of all finite sequences of elements of $\mathbb{N}$ is countable.
negative_passages.docid: 155168
negative_passages.text: Is the collection of finite subsets of $\mathbb{Z}$ countable?
negative_passages.docid: 63276
negative_passages.text: Is an arbitrary union of a chain of countable sets countable?
negative_passages.docid: 140168
negative_passages.text: What are the basis for co-countable and co-finite topologies
negative_passages.docid: 148992
negative_passages.text: A finite set is closed
negative_passages.docid: 67279
negative_passages.text: Is the union of finitely many open sets in an omega-cover contained within some member of the cover?
negative_passages.docid: 39956
negative_passages.text: Union of uncountable cardinals
negative_passages.docid: 36184
negative_passages.text: Countability of disjoint intervals
negative_passages.docid: 32774
negative_passages.text: Finite Cartesian Product of Countable sets is countable?
negative_passages.docid: 94825
negative_passages.text: Open set as a finite union of closed sets