We have the following indirect implication of form equivalence classes:
| Implication | Reference |
|---|---|
| 420 \(\Rightarrow\) 34 |
Metric spaces and the axiom of choice, De-la-Cruz-Hall-Howard-Keremedis-Rubin-2002A[2002A], Math. Logic Quart. |
Here are the links and statements of the form equivalence classes referenced above:
| Howard-Rubin Number | Statement |
|---|---|
| 420: | \(UT(\aleph_0\),\(\aleph_0\),cuf): The union of a denumerable set of denumerable sets is cuf. |
| 34: | \(\aleph_{1}\) is regular. |
Comment: