This non-implication,
Form 216 \( \not \Rightarrow \)
Form 9,
whose code is 4, is constructed around a proven non-implication as follows:
Hypothesis | Statement |
---|---|
Form 216 | <p> Every infinite tree has either an infinite chain or an infinite antichain. </p> |
Conclusion | Statement |
---|---|
Form 217 | <p> Every infinite partially ordered set has either an infinite chain or an infinite antichain. </p> |
The conclusion Form 216 \( \not \Rightarrow \) Form 9 then follows.
Finally, the
List of models where hypothesis is true and the conclusion is false:
Name | Statement |
---|---|
\(\cal N34\) Pincus' Model X | For each \(q\in\Bbb Q\), let \(C_q=\{a_q,b_q\}\), a pair of atoms and let \(A=\bigcup_{q\in\Bbb Q}C_q\) |