We have the following indirect implication of form equivalence classes:

319 \(\Rightarrow\) 320
given by the following sequence of implications, with a reference to its direct proof:

Implication Reference
319 \(\Rightarrow\) 320 note-20

Here are the links and statements of the form equivalence classes referenced above:

Howard-Rubin Number Statement
319:

Measurable cardinals are inaccessible.

320:

No successor cardinal, \(\aleph_{\alpha+1}\), is measurable.

Comment:

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