Hypothesis: HR 204:

For every infinite \(X\), there is a function from \(X\) onto \(2X\).

Conclusion: HR 88:

  \(C(\infty ,2)\):  Every family of pairs has a choice function.

List of models where hypothesis is true and the conclusion is false:

Name Statement
\(\cal M2\) Feferman's model Add a denumerable number of generic reals to the base model, but do not collect them
\(\cal N9\) Halpern/Howard Model \(A\) is a set of atoms with the structureof the set \( \{s : s:\omega\longrightarrow\omega \wedge (\exists n)(\forall j > n)(s_j = 0)\}\)

Code: 3

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