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(Exists (?T1 ?T2) (And (Term ?T1) (Term ?T2) (= ?X (Listof (Quote =) ?T1 ?T2)))) (Relsent ?X)
(<=> (Equation ?X) (And (Relsent ?X) (Exists (?T1 ?T2) (And (Term ?T1) (Term ?T2) (= ?X (Listof (Quote =) ?T1 ?T2))))))