| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							bnj978.1 | 
							   | 
						
						
							| 2 | 
							
								
							 | 
							bnj978.2 | 
							   | 
						
						
							| 3 | 
							
								1 2
							 | 
							sylbir | 
							   | 
						
						
							| 4 | 
							
								3
							 | 
							gen2 | 
							   | 
						
						
							| 5 | 
							
								
							 | 
							bnj253 | 
							   | 
						
						
							| 6 | 
							
								5
							 | 
							imbi1i | 
							   | 
						
						
							| 7 | 
							
								6
							 | 
							2albii | 
							   | 
						
						
							| 8 | 
							
								
							 | 
							3impexp | 
							   | 
						
						
							| 9 | 
							
								8
							 | 
							2albii | 
							   | 
						
						
							| 10 | 
							
								
							 | 
							19.21v | 
							   | 
						
						
							| 11 | 
							
								
							 | 
							19.21v | 
							   | 
						
						
							| 12 | 
							
								11
							 | 
							imbi2i | 
							   | 
						
						
							| 13 | 
							
								10 12
							 | 
							bitri | 
							   | 
						
						
							| 14 | 
							
								13
							 | 
							albii | 
							   | 
						
						
							| 15 | 
							
								
							 | 
							19.21v | 
							   | 
						
						
							| 16 | 
							
								
							 | 
							df-ral | 
							   | 
						
						
							| 17 | 
							
								16
							 | 
							bicomi | 
							   | 
						
						
							| 18 | 
							
								17
							 | 
							imbi2i | 
							   | 
						
						
							| 19 | 
							
								14 15 18
							 | 
							3bitri | 
							   | 
						
						
							| 20 | 
							
								7 9 19
							 | 
							3bitri | 
							   | 
						
						
							| 21 | 
							
								4 20
							 | 
							mpbi | 
							   | 
						
						
							| 22 | 
							
								
							 | 
							df-ss | 
							   | 
						
						
							| 23 | 
							
								22
							 | 
							ralbii | 
							   | 
						
						
							| 24 | 
							
								21 23
							 | 
							sylibr | 
							   | 
						
						
							| 25 | 
							
								
							 | 
							df-bnj19 | 
							   | 
						
						
							| 26 | 
							
								24 25
							 | 
							sylibr | 
							   |