| Step | Hyp | Ref | Expression | 
						
							| 1 |  | funcestrcsetc.e |  | 
						
							| 2 |  | funcestrcsetc.s |  | 
						
							| 3 |  | funcestrcsetc.b |  | 
						
							| 4 |  | funcestrcsetc.c |  | 
						
							| 5 |  | funcestrcsetc.u |  | 
						
							| 6 |  | funcestrcsetc.f |  | 
						
							| 7 |  | funcestrcsetc.g |  | 
						
							| 8 |  | f1oi |  | 
						
							| 9 |  | f1of |  | 
						
							| 10 | 8 9 | mp1i |  | 
						
							| 11 |  | elmapi |  | 
						
							| 12 |  | fvex |  | 
						
							| 13 |  | fvex |  | 
						
							| 14 | 12 13 | pm3.2i |  | 
						
							| 15 |  | elmapg |  | 
						
							| 16 | 15 | bicomd |  | 
						
							| 17 | 14 16 | mp1i |  | 
						
							| 18 | 17 | biimpa |  | 
						
							| 19 | 1 2 3 4 5 6 | funcestrcsetclem1 |  | 
						
							| 20 | 19 | adantrl |  | 
						
							| 21 | 1 2 3 4 5 6 | funcestrcsetclem1 |  | 
						
							| 22 | 21 | adantrr |  | 
						
							| 23 | 20 22 | oveq12d |  | 
						
							| 24 | 23 | adantr |  | 
						
							| 25 | 18 24 | eleqtrrd |  | 
						
							| 26 | 25 | ex |  | 
						
							| 27 | 11 26 | syl5 |  | 
						
							| 28 | 27 | ssrdv |  | 
						
							| 29 | 10 28 | fssd |  | 
						
							| 30 |  | eqid |  | 
						
							| 31 |  | eqid |  | 
						
							| 32 | 1 2 3 4 5 6 7 30 31 | funcestrcsetclem5 |  | 
						
							| 33 | 5 | adantr |  | 
						
							| 34 |  | eqid |  | 
						
							| 35 | 1 5 | estrcbas |  | 
						
							| 36 | 3 35 | eqtr4id |  | 
						
							| 37 | 36 | eleq2d |  | 
						
							| 38 | 37 | biimpcd |  | 
						
							| 39 | 38 | adantr |  | 
						
							| 40 | 39 | impcom |  | 
						
							| 41 | 36 | eleq2d |  | 
						
							| 42 | 41 | biimpd |  | 
						
							| 43 | 42 | adantld |  | 
						
							| 44 | 43 | imp |  | 
						
							| 45 | 1 33 34 40 44 30 31 | estrchom |  | 
						
							| 46 |  | eqid |  | 
						
							| 47 | 1 2 3 4 5 6 | funcestrcsetclem2 |  | 
						
							| 48 | 47 | adantrr |  | 
						
							| 49 | 1 2 3 4 5 6 | funcestrcsetclem2 |  | 
						
							| 50 | 49 | adantrl |  | 
						
							| 51 | 2 33 46 48 50 | setchom |  | 
						
							| 52 | 32 45 51 | feq123d |  | 
						
							| 53 | 29 52 | mpbird |  |