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: r_4 <-> q_17. p_1. ~q_17. ~r_4 -> s_3.
p_1 and ~q_17 can be inferred via the conjunction rule. ~q_17 and p_1 can be inferred via the conjunction rule. r_4 -> q_17 can be inferred via the biconditional elimination rule. q_17 -> r_4 can be inferred via the biconditional elimination rule. ~r_4 can be inferred via the biconditional elimination rule.