We have the following indirect implication of form equivalence classes:
Implication | Reference |
---|---|
16 \(\Rightarrow\) 352 |
On first and second countable spaces and the axiom of choice, Gutierres, G 2004, Topology and its Applications. |
352 \(\Rightarrow\) 31 |
On first and second countable spaces and the axiom of choice, Gutierres, G 2004, Topology and its Applications. |
31 \(\Rightarrow\) 32 |
L’axiome de M. Zermelo et son rˆole dans la th´eorie des ensembles et l’analyse, Sierpi'nski, W. 1918, Bull. Int. Acad. Sci. Cracovie Cl. Math. Nat. |
32 \(\Rightarrow\) 10 | clear |
10 \(\Rightarrow\) 423 | clear |
Here are the links and statements of the form equivalence classes referenced above:
Howard-Rubin Number | Statement |
---|---|
16: | \(C(\aleph_{0},\le 2^{\aleph_{0}})\): Every denumerable collection of non-empty sets each with power \(\le 2^{\aleph_{0}}\) has a choice function. |
352: | A countable product of second countable spaces is second countable. |
31: | \(UT(\aleph_{0},\aleph_{0},\aleph_{0})\): The countable union theorem: The union of a denumerable set of denumerable sets is denumerable. |
32: | \(C(\aleph_0,\le\aleph_0)\): Every denumerable set of non-empty countable sets has a choice function. |
10: | \(C(\aleph_{0},< \aleph_{0})\): Every denumerable family of non-empty finite sets has a choice function. |
423: | \(\forall n\in \omega-\{o,1\}\), \(C(\aleph_0, n)\) : For every \(n\in \omega - \{0,1\}\), every denumerable set of \(n\) element sets has a choice function. |
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