| Step | Hyp | Ref | Expression | 
						
							| 1 |  | llnexch.l |  | 
						
							| 2 |  | llnexch.j |  | 
						
							| 3 |  | llnexch.m |  | 
						
							| 4 |  | llnexch.a |  | 
						
							| 5 |  | llnexch.n |  | 
						
							| 6 | 1 2 3 4 5 | llnexchb2 |  | 
						
							| 7 |  | hllat |  | 
						
							| 8 | 7 | 3ad2ant1 |  | 
						
							| 9 |  | simp21 |  | 
						
							| 10 |  | eqid |  | 
						
							| 11 | 10 5 | llnbase |  | 
						
							| 12 | 9 11 | syl |  | 
						
							| 13 |  | simp22 |  | 
						
							| 14 | 10 5 | llnbase |  | 
						
							| 15 | 13 14 | syl |  | 
						
							| 16 | 10 1 3 | latmle2 |  | 
						
							| 17 | 8 12 15 16 | syl3anc |  | 
						
							| 18 |  | breq1 |  | 
						
							| 19 | 17 18 | syl5ibcom |  | 
						
							| 20 | 6 19 | sylbid |  |