We have the following indirect implication of form equivalence classes:
Implication | Reference |
---|---|
14 \(\Rightarrow\) 385 | clear |
385 \(\Rightarrow\) 406 |
The axiom of choice and two particular forms of Tychonoff theorem, Alas, O. T. 1969, Portugal. Math. |
Here are the links and statements of the form equivalence classes referenced above:
Howard-Rubin Number | Statement |
---|---|
14: | BPI: Every Boolean algebra has a prime ideal. |
385: | Countable Ultrafilter Theorem: Every proper filter with a countable base over a set \(S\) (in \({\cal P}(S)\)) can be extended to an ultrafilter. |
406: | The product of compact Hausdorf spaces is countably compact. Alas [1994]. |
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