The following diagram shows that 70 \(\not \Rightarrow\) 231 is a code 6 non-implication, and the theory of transferability then shows that it is actually a code 4. It follows that the non-implication 223 \( \not \Rightarrow \) 231 is not just a code 6 non-implication, but is also a code 4 non-implication.

231 This form is negation transferable
\(\Downarrow\)
99 \( \not \Rightarrow \) 18
\( \Downarrow \)
This form is transferable 70
\( \Downarrow \)
206
\( \Downarrow \)
223

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