This non-implication, Form 94 \( \not \Rightarrow \) Form 347, whose code is 4, is constructed around a proven non-implication as follows:

  • An (optional) implication of code 1 or code 2 is given. In this case, it's Code 2: 10187, whose string of implications is:
    8 \(\Rightarrow\) 94
  • A proven non-implication whose code is 3. In this case, it's Code 3: 74, Form 8 \( \not \Rightarrow \) Form 231 whose summary information is:
    Hypothesis Statement
    Form 8 <p> \(C(\aleph_{0},\infty)\): </p>

    Conclusion Statement
    Form 231 <p> \(UT(WO,WO,WO)\): The union of a well ordered collection of well orderable sets is well orderable. </p>

  • An (optional) implication of code 1 or code 2 is given. In this case, it's Code 2: 3276, whose string of implications is:
    347 \(\Rightarrow\) 40 \(\Rightarrow\) 231

The conclusion Form 94 \( \not \Rightarrow \) Form 347 then follows.

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

Name Statement
\(\cal M1(\langle\omega_1\rangle)\) Cohen/Pincus Model Pincus extends the methods of Cohen and adds a generic \(\omega_1\)-sequence, \(\langle I_{\alpha}: \alpha\in\omega_1\rangle\), of denumerable sets, where \(I_0\) is a denumerable set of generic reals, each \(I_{\alpha+1}\) is a generic set of enumerations of \(I_{\alpha}\), and for a limit ordinal \(\lambda\),\(I_{\lambda}\) is a generic set of choice functions for \(\{I_{\alpha}:\alpha \le \lambda\}\)
\(\cal M21\) Felgner's Model II Suppose \(\cal M \models ZF + V = L\). Define \(B=\{f: (\exists\alpha <\omega_1)f:\alpha\to\omega\}\)
\(\cal M43\) Pincus' Model V This is the model of <a href="/articles/Pincus-1977a">Pincus [1977a]</a>, Theorem 2.1 \((A)\)
\(\cal M44\) Pincus' Model VI This is the model of <a href="/articles/Pincus-1977a">Pincus [1977a]</a>, Theorem 2.1 \((B)\)
\(\cal M45\) Pincus' Model VII This is the model of <a href="/articles/Pincus-1977a">Pincus [1977a]</a>, Theorem 2.1 \((C)\)
\(\cal M46(m,M)\) Pincus' Model VIII This model depends on the natural number \(m\) and the set of natural numbers \(M\) which must satisfy Mostowski's condition: <ul type="none"> <li>\(S(M,m)\): For everydecomposition \(m = p_{1} + \ldots + p_{s}\) of \(m\) into a sum of primes at least one \(p_{i}\) divides an element of \(M\)</li> </ul>
\(\cal M47(n,M)\) Pincus' Model IX This is the model of <a href="/articles/Pincus-1977a">Pincus [1977a]</a>, Theorem 2.1 \((E)\)
\(\cal N2(\aleph_{\alpha})\) Jech's Model This is an extension of \(\cal N2\) in which \(A=\{a_{\gamma} : \gamma\in\omega_{\alpha}\}\); \(B\) is the corresponding set of \(\aleph_{\alpha}\) pairs of elements of \(A\); \(\cal G\)is the group of all permutations on \(A\) that leave \(B\) point-wise fixed;and \(S\) is the set of all subsets of \(A\) of cardinality less than\(\aleph_{\alpha}\)
\(\cal N15\) Brunner/Howard Model I \(A=\{a_{i,\alpha}: i\in\omega\wedge\alpha\in\omega_1\}\)

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