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_15: R_15(x_15) -> S_15(x_15). S_15(a_15) -> p. R_15(a_15) or ~p.
p -> R_15(a_15) can be inferred via the rewriting rule.