We have the following indirect implication of form equivalence classes:
			
| Implication | Reference | 
|---|---|
| 43 \(\Rightarrow\) 8 | clear | 
| 8 \(\Rightarrow\) 9 | Was sind und was sollen die Zollen?, Dedekind, [1888] | 
| 9 \(\Rightarrow\) 98 | clear | 
Here are the links and statements of the form equivalence classes referenced above:
| Howard-Rubin Number | Statement | 
|---|---|
| 43: | \(DC(\omega)\) (DC), Principle of Dependent Choices: If \(S\) is a relation on a non-empty set \(A\) and \((\forall x\in A) (\exists y\in A)(x S y)\) then there is a sequence \(a(0), a(1), a(2), \ldots\) of elements of \(A\) such that \((\forall n\in\omega)(a(n)\mathrel S a(n+1))\). See Tarski [1948], p 96, Levy [1964], p. 136. | 
| 8: | \(C(\aleph_{0},\infty)\): | 
| 9: | Finite \(\Leftrightarrow\) Dedekind finite: \(W_{\aleph_{0}}\) Jech [1973b]: \(E(I,IV)\) Howard/Yorke [1989]): Every Dedekind finite set is finite. | 
| 98: | The set of all finite subsets of a Dedekind finite set is Dedekind finite. Jech [1973b] p 161 prob 11.5. | 
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