We have the following indirect implication of form equivalence classes:
| Implication | Reference |
|---|---|
| 31 \(\Rightarrow\) 34 | clear |
| 34 \(\Rightarrow\) 104 | clear |
Here are the links and statements of the form equivalence classes referenced above:
| Howard-Rubin Number | Statement |
|---|---|
| 31: | \(UT(\aleph_{0},\aleph_{0},\aleph_{0})\): The countable union theorem: The union of a denumerable set of denumerable sets is denumerable. |
| 34: | \(\aleph_{1}\) is regular. |
| 104: | There is a regular uncountable aleph. Jech [1966b], p 165 prob 11.26. |
Comment: