| Step | Hyp | Ref | Expression | 
						
							| 1 |  | grtri.v |  | 
						
							| 2 |  | grtri.e |  | 
						
							| 3 |  | elfvex | Could not format  ( T e. ( GrTriangles ` G ) -> G e. _V ) : No typesetting found for |- ( T e. ( GrTriangles ` G ) -> G e. _V ) with typecode |- | 
						
							| 4 | 1 2 | grtri | Could not format  ( G e. _V -> ( GrTriangles ` G ) = { t e. ~P V | E. f ( f : ( 0 ..^ 3 ) -1-1-onto-> t /\ ( { ( f ` 0 ) , ( f ` 1 ) } e. E /\ { ( f ` 0 ) , ( f ` 2 ) } e. E /\ { ( f ` 1 ) , ( f ` 2 ) } e. E ) ) } ) : No typesetting found for |- ( G e. _V -> ( GrTriangles ` G ) = { t e. ~P V | E. f ( f : ( 0 ..^ 3 ) -1-1-onto-> t /\ ( { ( f ` 0 ) , ( f ` 1 ) } e. E /\ { ( f ` 0 ) , ( f ` 2 ) } e. E /\ { ( f ` 1 ) , ( f ` 2 ) } e. E ) ) } ) with typecode |- | 
						
							| 5 | 3 4 | syl | Could not format  ( T e. ( GrTriangles ` G ) -> ( GrTriangles ` G ) = { t e. ~P V | E. f ( f : ( 0 ..^ 3 ) -1-1-onto-> t /\ ( { ( f ` 0 ) , ( f ` 1 ) } e. E /\ { ( f ` 0 ) , ( f ` 2 ) } e. E /\ { ( f ` 1 ) , ( f ` 2 ) } e. E ) ) } ) : No typesetting found for |- ( T e. ( GrTriangles ` G ) -> ( GrTriangles ` G ) = { t e. ~P V | E. f ( f : ( 0 ..^ 3 ) -1-1-onto-> t /\ ( { ( f ` 0 ) , ( f ` 1 ) } e. E /\ { ( f ` 0 ) , ( f ` 2 ) } e. E /\ { ( f ` 1 ) , ( f ` 2 ) } e. E ) ) } ) with typecode |- | 
						
							| 6 | 5 | eleq2d | Could not format  ( T e. ( GrTriangles ` G ) -> ( T e. ( GrTriangles ` G ) <-> T e. { t e. ~P V | E. f ( f : ( 0 ..^ 3 ) -1-1-onto-> t /\ ( { ( f ` 0 ) , ( f ` 1 ) } e. E /\ { ( f ` 0 ) , ( f ` 2 ) } e. E /\ { ( f ` 1 ) , ( f ` 2 ) } e. E ) ) } ) ) : No typesetting found for |- ( T e. ( GrTriangles ` G ) -> ( T e. ( GrTriangles ` G ) <-> T e. { t e. ~P V | E. f ( f : ( 0 ..^ 3 ) -1-1-onto-> t /\ ( { ( f ` 0 ) , ( f ` 1 ) } e. E /\ { ( f ` 0 ) , ( f ` 2 ) } e. E /\ { ( f ` 1 ) , ( f ` 2 ) } e. E ) ) } ) ) with typecode |- | 
						
							| 7 |  | f1oeq3 |  | 
						
							| 8 | 7 | anbi1d |  | 
						
							| 9 | 8 | exbidv |  | 
						
							| 10 | 9 | elrab |  | 
						
							| 11 | 6 10 | bitrdi | Could not format  ( T e. ( GrTriangles ` G ) -> ( T e. ( GrTriangles ` G ) <-> ( T e. ~P V /\ E. f ( f : ( 0 ..^ 3 ) -1-1-onto-> T /\ ( { ( f ` 0 ) , ( f ` 1 ) } e. E /\ { ( f ` 0 ) , ( f ` 2 ) } e. E /\ { ( f ` 1 ) , ( f ` 2 ) } e. E ) ) ) ) ) : No typesetting found for |- ( T e. ( GrTriangles ` G ) -> ( T e. ( GrTriangles ` G ) <-> ( T e. ~P V /\ E. f ( f : ( 0 ..^ 3 ) -1-1-onto-> T /\ ( { ( f ` 0 ) , ( f ` 1 ) } e. E /\ { ( f ` 0 ) , ( f ` 2 ) } e. E /\ { ( f ` 1 ) , ( f ` 2 ) } e. E ) ) ) ) ) with typecode |- | 
						
							| 12 |  | ovexd |  | 
						
							| 13 |  | simpr |  | 
						
							| 14 | 12 13 | hasheqf1od |  | 
						
							| 15 |  | eqcom |  | 
						
							| 16 |  | 3nn0 |  | 
						
							| 17 |  | hashfzo0 |  | 
						
							| 18 | 16 17 | mp1i |  | 
						
							| 19 | 18 | eqeq2d |  | 
						
							| 20 | 15 19 | bitrid |  | 
						
							| 21 |  | hash3tpb |  | 
						
							| 22 | 21 | adantr |  | 
						
							| 23 | 22 | biimpa |  | 
						
							| 24 |  | elpwi |  | 
						
							| 25 |  | ss2rexv |  | 
						
							| 26 |  | ssrexv |  | 
						
							| 27 | 26 | reximdv |  | 
						
							| 28 | 27 | reximdv |  | 
						
							| 29 | 25 28 | syld |  | 
						
							| 30 | 24 29 | syl |  | 
						
							| 31 | 30 | adantr |  | 
						
							| 32 | 31 | adantr |  | 
						
							| 33 |  | simprr |  | 
						
							| 34 |  | simp-5r |  | 
						
							| 35 |  | f1oeq3 |  | 
						
							| 36 |  | grtriproplem |  | 
						
							| 37 | 36 | 2a1d |  | 
						
							| 38 | 37 | ex |  | 
						
							| 39 | 38 | a1d |  | 
						
							| 40 | 35 39 | biimtrdi |  | 
						
							| 41 | 40 | adantld |  | 
						
							| 42 | 41 | imp4c |  | 
						
							| 43 | 42 | imp4c |  | 
						
							| 44 | 43 | adantl |  | 
						
							| 45 | 44 | impcom |  | 
						
							| 46 | 33 34 45 | 3jca |  | 
						
							| 47 | 46 | ex |  | 
						
							| 48 | 47 | reximdva |  | 
						
							| 49 | 48 | reximdvva |  | 
						
							| 50 | 49 | ex |  | 
						
							| 51 | 50 | com23 |  | 
						
							| 52 | 32 51 | syld |  | 
						
							| 53 | 23 52 | mpd |  | 
						
							| 54 | 53 | ex |  | 
						
							| 55 | 20 54 | sylbid |  | 
						
							| 56 | 14 55 | mpd |  | 
						
							| 57 | 56 | expimpd |  | 
						
							| 58 | 57 | exlimdv |  | 
						
							| 59 | 58 | imp |  | 
						
							| 60 | 11 59 | biimtrdi | Could not format  ( T e. ( GrTriangles ` G ) -> ( T e. ( GrTriangles ` G ) -> E. x e. V E. y e. V E. z e. V ( T = { x , y , z } /\ ( # ` T ) = 3 /\ ( { x , y } e. E /\ { x , z } e. E /\ { y , z } e. E ) ) ) ) : No typesetting found for |- ( T e. ( GrTriangles ` G ) -> ( T e. ( GrTriangles ` G ) -> E. x e. V E. y e. V E. z e. V ( T = { x , y , z } /\ ( # ` T ) = 3 /\ ( { x , y } e. E /\ { x , z } e. E /\ { y , z } e. E ) ) ) ) with typecode |- | 
						
							| 61 | 60 | pm2.43i | Could not format  ( T e. ( GrTriangles ` G ) -> E. x e. V E. y e. V E. z e. V ( T = { x , y , z } /\ ( # ` T ) = 3 /\ ( { x , y } e. E /\ { x , z } e. E /\ { y , z } e. E ) ) ) : No typesetting found for |- ( T e. ( GrTriangles ` G ) -> E. x e. V E. y e. V E. z e. V ( T = { x , y , z } /\ ( # ` T ) = 3 /\ ( { x , y } e. E /\ { x , z } e. E /\ { y , z } e. E ) ) ) with typecode |- |