| Step | Hyp | Ref | Expression | 
						
							| 1 |  | znval.s |  | 
						
							| 2 |  | znval.u |  | 
						
							| 3 |  | znval.y |  | 
						
							| 4 |  | znval.f |  | 
						
							| 5 |  | znval.w |  | 
						
							| 6 |  | znval.l |  | 
						
							| 7 |  | zringring |  | 
						
							| 8 | 7 | a1i |  | 
						
							| 9 |  | ovexd |  | 
						
							| 10 |  | id |  | 
						
							| 11 |  | simpr |  | 
						
							| 12 | 11 | fveq2d |  | 
						
							| 13 | 12 1 | eqtr4di |  | 
						
							| 14 |  | simpl |  | 
						
							| 15 | 14 | sneqd |  | 
						
							| 16 | 13 15 | fveq12d |  | 
						
							| 17 | 11 16 | oveq12d |  | 
						
							| 18 | 11 17 | oveq12d |  | 
						
							| 19 | 18 2 | eqtr4di |  | 
						
							| 20 | 10 19 | sylan9eqr |  | 
						
							| 21 |  | fvex |  | 
						
							| 22 | 21 | resex |  | 
						
							| 23 | 22 | a1i |  | 
						
							| 24 |  | id |  | 
						
							| 25 | 20 | fveq2d |  | 
						
							| 26 |  | simpll |  | 
						
							| 27 | 26 | eqeq1d |  | 
						
							| 28 | 26 | oveq2d |  | 
						
							| 29 | 27 28 | ifbieq2d |  | 
						
							| 30 | 29 5 | eqtr4di |  | 
						
							| 31 | 25 30 | reseq12d |  | 
						
							| 32 | 31 4 | eqtr4di |  | 
						
							| 33 | 24 32 | sylan9eqr |  | 
						
							| 34 | 33 | coeq1d |  | 
						
							| 35 | 33 | cnveqd |  | 
						
							| 36 | 34 35 | coeq12d |  | 
						
							| 37 | 36 6 | eqtr4di |  | 
						
							| 38 | 23 37 | csbied |  | 
						
							| 39 | 38 | opeq2d |  | 
						
							| 40 | 20 39 | oveq12d |  | 
						
							| 41 | 9 40 | csbied |  | 
						
							| 42 | 8 41 | csbied |  | 
						
							| 43 |  | df-zn |  | 
						
							| 44 |  | ovex |  | 
						
							| 45 | 42 43 44 | fvmpt |  | 
						
							| 46 | 3 45 | eqtrid |  |