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Proof WritingChallengeExistence, Uniqueness and Counterexamples

Existence, Uniqueness and Counterexamples · Challenge problem

A relation RR on {1,2,3}\{1, 2, 3\} is any set of ordered pairs. For how many relations is "∀x ∃y:(x,y)∈R\forall x\ \exists y: (x, y) \in R" true but "∃y ∀x:(x,y)∈R\exists y\ \forall x: (x, y) \in R" false?