Complement

$\textbf{Complement} \; A \; B \; R := \top_{A,B} - R$

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$\textbf{Relation} \; A \; B \; R$

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Notation.

1. $\textbf{Complement} \; A \; B \; R$ can be written $\textbf{Complement} \; R$ when $A$ and $B$are clear from the context.

2. $\textbf{Complement} \; R$ can be written symbolically as $\neg R$ or $\overline{R}$.

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fun Co(A,B: set univ, R: A->B) : A->B {
  (A->B) - R
}