| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							zrinitorngc.u | 
							   | 
						
						
							| 2 | 
							
								
							 | 
							zrinitorngc.c | 
							   | 
						
						
							| 3 | 
							
								
							 | 
							zrinitorngc.z | 
							   | 
						
						
							| 4 | 
							
								
							 | 
							zrinitorngc.e | 
							   | 
						
						
							| 5 | 
							
								1 2 3 4
							 | 
							zrinitorngc | 
							   | 
						
						
							| 6 | 
							
								1 2 3 4
							 | 
							zrtermorngc | 
							   | 
						
						
							| 7 | 
							
								
							 | 
							eqid | 
							   | 
						
						
							| 8 | 
							
								
							 | 
							eqid | 
							   | 
						
						
							| 9 | 
							
								2
							 | 
							rngccat | 
							   | 
						
						
							| 10 | 
							
								1 9
							 | 
							syl | 
							   | 
						
						
							| 11 | 
							
								3
							 | 
							eldifad | 
							   | 
						
						
							| 12 | 
							
								
							 | 
							ringrng | 
							   | 
						
						
							| 13 | 
							
								11 12
							 | 
							syl | 
							   | 
						
						
							| 14 | 
							
								4 13
							 | 
							elind | 
							   | 
						
						
							| 15 | 
							
								2 7 1
							 | 
							rngcbas | 
							   | 
						
						
							| 16 | 
							
								14 15
							 | 
							eleqtrrd | 
							   | 
						
						
							| 17 | 
							
								7 8 10 16
							 | 
							iszeroo | 
							   | 
						
						
							| 18 | 
							
								5 6 17
							 | 
							mpbir2and | 
							   |