Form equivalence class Howard-Rubin Number: 14

Statement:  Cowen-Engler Lemma:  Let \(\Lambda\) and \(X\) be sets.Let \(\Phi\) be a family of functions from subsets of \(\Lambda\) into X.Assume\itemitem{(a)} \(\Phi(\lambda) = \{f(\lambda ): f\in\Phi\) and \(\lambda\in\)dom \(f\}\) is finite for each \(\lambda\in \Lambda\),\itemitem{(b)} each finite \(S\subseteq\Lambda\) is the domain of atleast one \(f\in\Phi\),  and\itemitem{(c)} \(\Phi\) has finite character, (that is, a function \(f\) froma subset of \(\Lambda\) into \(X\) is in \(\Phi\) if and only if every finitesubset of \(f\) is in \(\Phi\)).\item{}Then at least one \(f\in\Phi\) has domain \(\Lambda\). Schechter [1996a]. (See [14 I].)

Howard-Rubin number: 14 X

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