We have the following indirect implication of form equivalence classes:

247 \(\Rightarrow\) 247
given by the following sequence of implications, with a reference to its direct proof:

Implication Reference
247 \(\Rightarrow\) 247

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

Howard-Rubin Number Statement
247:

Every atomless Boolean algebra is Dedekind infinite.  \ac{Plotkin} \cite{1976}, notes 86 and 94.

247:

Every atomless Boolean algebra is Dedekind infinite.  \ac{Plotkin} \cite{1976}, notes 86 and 94.

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