| 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 | 
							   |