We have the following indirect implication of form equivalence classes:
| Implication | Reference |
|---|---|
| 8 \(\Rightarrow\) 421 |
Unions and the axiom of choice, De-la-Cruz-Hall-Howard-Keremedis-Rubin-2002B[2002B], Math. Logic Quart. |
Here are the links and statements of the form equivalence classes referenced above:
| Howard-Rubin Number | Statement |
|---|---|
| 8: | \(C(\aleph_{0},\infty)\): |
| 421: | \(UT(\aleph_0,WO,WO)\): The union of a denumerable set of well orderable sets can be well ordered. |
Comment: