Consider the following premises. p_1 <-> q. p_16 -> u_1. u_1 -> p_1. q <-> p_16. Can we infer p_16 <-> q from them?
 From p_16 -> u_1, u_1 -> p_1 we can infer p_16 -> p_1. From q <-> p_16 we can infer q -> p_16. From p_1 <-> q we can infer p_1 -> q. From p_16 -> p_1, p_1 -> q we can infer p_16 -> q. Finally, from p_16 -> q, q -> p_16 we can infer p_16 <-> q. Therefore, the answer is yes.