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: p_4 <-> S_17(a_17). ~R_17(a_17). forall x_17: R_17(x_17) or S_17(x_17).
p_4 -> S_17(a_17) can be inferred via the biconditional elimination rule. S_17(a_17) -> p_4 can be inferred via the biconditional elimination rule.