What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: forall x_16: T(x_16) <-> S_16(x_16). T(j_3) <-> R_21(a_21). forall x_21: ~R_21(x_21). w_1.
T(j_3) -> R_21(a_21) can be inferred via the biconditional elimination rule. R_21(a_21) -> T(j_3) can be inferred via the biconditional elimination rule. forall x_16: T(x_16) -> S_16(x_16) can be inferred via the universal biconditional elimination rule. forall x_16: S_16(x_16) -> T(x_16) can be inferred via the universal biconditional elimination rule.