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_1 -> p. p -> p_11. p_11 -> p. p_11 -> p_1.
p_1 -> p_11 can be inferred via the transitivity rule. p -> p_1 can be inferred via the transitivity rule. p_11 -> p can be inferred via the transitivity rule. p <-> p_11 can be inferred via the biconditional introduction rule. p_11 <-> p can be inferred via the biconditional introduction rule.