| Step | Hyp | Ref | Expression | 
						
							| 1 |  | basvtxval.s |  |-  ( ph -> G Struct X ) | 
						
							| 2 |  | basvtxval.d |  |-  ( ph -> 2 <_ ( # ` dom G ) ) | 
						
							| 3 |  | edgfiedgval.e |  |-  ( ph -> E e. Y ) | 
						
							| 4 |  | edgfiedgval.f |  |-  ( ph -> <. ( .ef ` ndx ) , E >. e. G ) | 
						
							| 5 |  | structn0fun |  |-  ( G Struct X -> Fun ( G \ { (/) } ) ) | 
						
							| 6 | 1 5 | syl |  |-  ( ph -> Fun ( G \ { (/) } ) ) | 
						
							| 7 |  | funiedgdmge2val |  |-  ( ( Fun ( G \ { (/) } ) /\ 2 <_ ( # ` dom G ) ) -> ( iEdg ` G ) = ( .ef ` G ) ) | 
						
							| 8 | 6 2 7 | syl2anc |  |-  ( ph -> ( iEdg ` G ) = ( .ef ` G ) ) | 
						
							| 9 |  | edgfid |  |-  .ef = Slot ( .ef ` ndx ) | 
						
							| 10 |  | structex |  |-  ( G Struct X -> G e. _V ) | 
						
							| 11 | 1 10 | syl |  |-  ( ph -> G e. _V ) | 
						
							| 12 |  | structfung |  |-  ( G Struct X -> Fun `' `' G ) | 
						
							| 13 | 1 12 | syl |  |-  ( ph -> Fun `' `' G ) | 
						
							| 14 | 9 11 13 4 3 | strfv2d |  |-  ( ph -> E = ( .ef ` G ) ) | 
						
							| 15 | 8 14 | eqtr4d |  |-  ( ph -> ( iEdg ` G ) = E ) |