Consider the following premises. ~p or r_16. p or t. ~t. u_2 <-> r_16. Can we infer ~u_2 from them?
 From p or t, ~p or r_16 we can infer t or r_16. From u_2 <-> r_16 we can infer r_16 -> u_2. From t or r_16, ~t we can infer r_16. Finally, from r_16 -> u_2, r_16 we can infer u_2, which contradicts ~u_2. Therefore, the answer is no.