Implications

We have the following indirect implication of form equivalence classes:

85 \(\Rightarrow\) 119
given by the following sequence of implications, with a reference to its direct proof:

Implication Reference
85 \(\Rightarrow\) 32 clear
32 \(\Rightarrow\) 119 clear

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

Howard-Rubin Number Statement
85:

\(C(\infty,\aleph_{0})\):  Every family of denumerable sets has  a choice function.  Jech [1973b] p 115 prob 7.13.

32:

\(C(\aleph_0,\le\aleph_0)\): Every denumerable set of non-empty countable sets  has a choice function.

119:

van Douwen's choice principle: \(C(\aleph_{0}\),uniformly orderable with order type of the integers): Suppose \(\{ A_{i}: i\in\omega\}\) is a set and there is a function \(f\) such that for each \(i\in\omega,\ f(i)\) is an ordering of \(A_{i}\) of type \(\omega^{*}+\omega\) (the usual ordering of the integers), then \(\{A_{i}: i\in\omega\}\) has a choice function.

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