| Step | Hyp | Ref | Expression | 
						
							| 1 |  | funcestrcsetc.e |  |-  E = ( ExtStrCat ` U ) | 
						
							| 2 |  | funcestrcsetc.s |  |-  S = ( SetCat ` U ) | 
						
							| 3 |  | funcestrcsetc.b |  |-  B = ( Base ` E ) | 
						
							| 4 |  | funcestrcsetc.c |  |-  C = ( Base ` S ) | 
						
							| 5 |  | funcestrcsetc.u |  |-  ( ph -> U e. WUni ) | 
						
							| 6 |  | funcestrcsetc.f |  |-  ( ph -> F = ( x e. B |-> ( Base ` x ) ) ) | 
						
							| 7 |  | funcestrcsetc.g |  |-  ( ph -> G = ( x e. B , y e. B |-> ( _I |` ( ( Base ` y ) ^m ( Base ` x ) ) ) ) ) | 
						
							| 8 | 1 2 3 4 5 6 7 | funcestrcsetc |  |-  ( ph -> F ( E Func S ) G ) | 
						
							| 9 | 1 2 3 4 5 6 7 | funcestrcsetclem8 |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( a G b ) : ( a ( Hom ` E ) b ) --> ( ( F ` a ) ( Hom ` S ) ( F ` b ) ) ) | 
						
							| 10 | 5 | adantr |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> U e. WUni ) | 
						
							| 11 |  | eqid |  |-  ( Hom ` S ) = ( Hom ` S ) | 
						
							| 12 | 1 2 3 4 5 6 | funcestrcsetclem2 |  |-  ( ( ph /\ a e. B ) -> ( F ` a ) e. U ) | 
						
							| 13 | 12 | adantrr |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( F ` a ) e. U ) | 
						
							| 14 | 1 2 3 4 5 6 | funcestrcsetclem2 |  |-  ( ( ph /\ b e. B ) -> ( F ` b ) e. U ) | 
						
							| 15 | 14 | adantrl |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( F ` b ) e. U ) | 
						
							| 16 | 2 10 11 13 15 | elsetchom |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( h e. ( ( F ` a ) ( Hom ` S ) ( F ` b ) ) <-> h : ( F ` a ) --> ( F ` b ) ) ) | 
						
							| 17 | 1 2 3 4 5 6 | funcestrcsetclem1 |  |-  ( ( ph /\ a e. B ) -> ( F ` a ) = ( Base ` a ) ) | 
						
							| 18 | 17 | adantrr |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( F ` a ) = ( Base ` a ) ) | 
						
							| 19 | 1 2 3 4 5 6 | funcestrcsetclem1 |  |-  ( ( ph /\ b e. B ) -> ( F ` b ) = ( Base ` b ) ) | 
						
							| 20 | 19 | adantrl |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( F ` b ) = ( Base ` b ) ) | 
						
							| 21 | 18 20 | feq23d |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( h : ( F ` a ) --> ( F ` b ) <-> h : ( Base ` a ) --> ( Base ` b ) ) ) | 
						
							| 22 | 16 21 | bitrd |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( h e. ( ( F ` a ) ( Hom ` S ) ( F ` b ) ) <-> h : ( Base ` a ) --> ( Base ` b ) ) ) | 
						
							| 23 |  | fvex |  |-  ( Base ` b ) e. _V | 
						
							| 24 |  | fvex |  |-  ( Base ` a ) e. _V | 
						
							| 25 | 23 24 | pm3.2i |  |-  ( ( Base ` b ) e. _V /\ ( Base ` a ) e. _V ) | 
						
							| 26 |  | elmapg |  |-  ( ( ( Base ` b ) e. _V /\ ( Base ` a ) e. _V ) -> ( h e. ( ( Base ` b ) ^m ( Base ` a ) ) <-> h : ( Base ` a ) --> ( Base ` b ) ) ) | 
						
							| 27 | 25 26 | mp1i |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( h e. ( ( Base ` b ) ^m ( Base ` a ) ) <-> h : ( Base ` a ) --> ( Base ` b ) ) ) | 
						
							| 28 | 27 | biimpar |  |-  ( ( ( ph /\ ( a e. B /\ b e. B ) ) /\ h : ( Base ` a ) --> ( Base ` b ) ) -> h e. ( ( Base ` b ) ^m ( Base ` a ) ) ) | 
						
							| 29 |  | equequ2 |  |-  ( k = h -> ( h = k <-> h = h ) ) | 
						
							| 30 | 29 | adantl |  |-  ( ( ( ( ph /\ ( a e. B /\ b e. B ) ) /\ h : ( Base ` a ) --> ( Base ` b ) ) /\ k = h ) -> ( h = k <-> h = h ) ) | 
						
							| 31 |  | eqidd |  |-  ( ( ( ph /\ ( a e. B /\ b e. B ) ) /\ h : ( Base ` a ) --> ( Base ` b ) ) -> h = h ) | 
						
							| 32 | 28 30 31 | rspcedvd |  |-  ( ( ( ph /\ ( a e. B /\ b e. B ) ) /\ h : ( Base ` a ) --> ( Base ` b ) ) -> E. k e. ( ( Base ` b ) ^m ( Base ` a ) ) h = k ) | 
						
							| 33 |  | eqid |  |-  ( Base ` a ) = ( Base ` a ) | 
						
							| 34 |  | eqid |  |-  ( Base ` b ) = ( Base ` b ) | 
						
							| 35 | 1 2 3 4 5 6 7 33 34 | funcestrcsetclem6 |  |-  ( ( ph /\ ( a e. B /\ b e. B ) /\ k e. ( ( Base ` b ) ^m ( Base ` a ) ) ) -> ( ( a G b ) ` k ) = k ) | 
						
							| 36 | 35 | 3expa |  |-  ( ( ( ph /\ ( a e. B /\ b e. B ) ) /\ k e. ( ( Base ` b ) ^m ( Base ` a ) ) ) -> ( ( a G b ) ` k ) = k ) | 
						
							| 37 | 36 | eqeq2d |  |-  ( ( ( ph /\ ( a e. B /\ b e. B ) ) /\ k e. ( ( Base ` b ) ^m ( Base ` a ) ) ) -> ( h = ( ( a G b ) ` k ) <-> h = k ) ) | 
						
							| 38 | 37 | rexbidva |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( E. k e. ( ( Base ` b ) ^m ( Base ` a ) ) h = ( ( a G b ) ` k ) <-> E. k e. ( ( Base ` b ) ^m ( Base ` a ) ) h = k ) ) | 
						
							| 39 | 38 | adantr |  |-  ( ( ( ph /\ ( a e. B /\ b e. B ) ) /\ h : ( Base ` a ) --> ( Base ` b ) ) -> ( E. k e. ( ( Base ` b ) ^m ( Base ` a ) ) h = ( ( a G b ) ` k ) <-> E. k e. ( ( Base ` b ) ^m ( Base ` a ) ) h = k ) ) | 
						
							| 40 | 32 39 | mpbird |  |-  ( ( ( ph /\ ( a e. B /\ b e. B ) ) /\ h : ( Base ` a ) --> ( Base ` b ) ) -> E. k e. ( ( Base ` b ) ^m ( Base ` a ) ) h = ( ( a G b ) ` k ) ) | 
						
							| 41 |  | eqid |  |-  ( Hom ` E ) = ( Hom ` E ) | 
						
							| 42 | 1 5 | estrcbas |  |-  ( ph -> U = ( Base ` E ) ) | 
						
							| 43 | 3 42 | eqtr4id |  |-  ( ph -> B = U ) | 
						
							| 44 | 43 | eleq2d |  |-  ( ph -> ( a e. B <-> a e. U ) ) | 
						
							| 45 | 44 | biimpcd |  |-  ( a e. B -> ( ph -> a e. U ) ) | 
						
							| 46 | 45 | adantr |  |-  ( ( a e. B /\ b e. B ) -> ( ph -> a e. U ) ) | 
						
							| 47 | 46 | impcom |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> a e. U ) | 
						
							| 48 | 43 | eleq2d |  |-  ( ph -> ( b e. B <-> b e. U ) ) | 
						
							| 49 | 48 | biimpcd |  |-  ( b e. B -> ( ph -> b e. U ) ) | 
						
							| 50 | 49 | adantl |  |-  ( ( a e. B /\ b e. B ) -> ( ph -> b e. U ) ) | 
						
							| 51 | 50 | impcom |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> b e. U ) | 
						
							| 52 | 1 10 41 47 51 33 34 | estrchom |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( a ( Hom ` E ) b ) = ( ( Base ` b ) ^m ( Base ` a ) ) ) | 
						
							| 53 | 52 | rexeqdv |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( E. k e. ( a ( Hom ` E ) b ) h = ( ( a G b ) ` k ) <-> E. k e. ( ( Base ` b ) ^m ( Base ` a ) ) h = ( ( a G b ) ` k ) ) ) | 
						
							| 54 | 53 | adantr |  |-  ( ( ( ph /\ ( a e. B /\ b e. B ) ) /\ h : ( Base ` a ) --> ( Base ` b ) ) -> ( E. k e. ( a ( Hom ` E ) b ) h = ( ( a G b ) ` k ) <-> E. k e. ( ( Base ` b ) ^m ( Base ` a ) ) h = ( ( a G b ) ` k ) ) ) | 
						
							| 55 | 40 54 | mpbird |  |-  ( ( ( ph /\ ( a e. B /\ b e. B ) ) /\ h : ( Base ` a ) --> ( Base ` b ) ) -> E. k e. ( a ( Hom ` E ) b ) h = ( ( a G b ) ` k ) ) | 
						
							| 56 | 55 | ex |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( h : ( Base ` a ) --> ( Base ` b ) -> E. k e. ( a ( Hom ` E ) b ) h = ( ( a G b ) ` k ) ) ) | 
						
							| 57 | 22 56 | sylbid |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( h e. ( ( F ` a ) ( Hom ` S ) ( F ` b ) ) -> E. k e. ( a ( Hom ` E ) b ) h = ( ( a G b ) ` k ) ) ) | 
						
							| 58 | 57 | ralrimiv |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> A. h e. ( ( F ` a ) ( Hom ` S ) ( F ` b ) ) E. k e. ( a ( Hom ` E ) b ) h = ( ( a G b ) ` k ) ) | 
						
							| 59 |  | dffo3 |  |-  ( ( a G b ) : ( a ( Hom ` E ) b ) -onto-> ( ( F ` a ) ( Hom ` S ) ( F ` b ) ) <-> ( ( a G b ) : ( a ( Hom ` E ) b ) --> ( ( F ` a ) ( Hom ` S ) ( F ` b ) ) /\ A. h e. ( ( F ` a ) ( Hom ` S ) ( F ` b ) ) E. k e. ( a ( Hom ` E ) b ) h = ( ( a G b ) ` k ) ) ) | 
						
							| 60 | 9 58 59 | sylanbrc |  |-  ( ( ph /\ ( a e. B /\ b e. B ) ) -> ( a G b ) : ( a ( Hom ` E ) b ) -onto-> ( ( F ` a ) ( Hom ` S ) ( F ` b ) ) ) | 
						
							| 61 | 60 | ralrimivva |  |-  ( ph -> A. a e. B A. b e. B ( a G b ) : ( a ( Hom ` E ) b ) -onto-> ( ( F ` a ) ( Hom ` S ) ( F ` b ) ) ) | 
						
							| 62 | 3 11 41 | isfull2 |  |-  ( F ( E Full S ) G <-> ( F ( E Func S ) G /\ A. a e. B A. b e. B ( a G b ) : ( a ( Hom ` E ) b ) -onto-> ( ( F ` a ) ( Hom ` S ) ( F ` b ) ) ) ) | 
						
							| 63 | 8 61 62 | sylanbrc |  |-  ( ph -> F ( E Full S ) G ) |