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: s_2 -> s. s -> s_3. s_3 -> r_2. r_2 -> s_2.
s_2 -> s_3 can be inferred via the transitivity rule. s -> r_2 can be inferred via the transitivity rule. s_3 -> s_2 can be inferred via the transitivity rule. r_2 -> s can be inferred via the transitivity rule.