| Step | Hyp | Ref | Expression | 
						
							| 1 |  | om2noseq.1 |  |-  ( ph -> C e. No ) | 
						
							| 2 |  | om2noseq.2 |  |-  ( ph -> G = ( rec ( ( x e. _V |-> ( x +s 1s ) ) , C ) |` _om ) ) | 
						
							| 3 |  | om2noseq.3 |  |-  ( ph -> Z = ( rec ( ( x e. _V |-> ( x +s 1s ) ) , C ) " _om ) ) | 
						
							| 4 |  | frfnom |  |-  ( rec ( ( x e. _V |-> ( x +s 1s ) ) , C ) |` _om ) Fn _om | 
						
							| 5 | 2 | fneq1d |  |-  ( ph -> ( G Fn _om <-> ( rec ( ( x e. _V |-> ( x +s 1s ) ) , C ) |` _om ) Fn _om ) ) | 
						
							| 6 | 4 5 | mpbiri |  |-  ( ph -> G Fn _om ) | 
						
							| 7 |  | df-ima |  |-  ( rec ( ( x e. _V |-> ( x +s 1s ) ) , C ) " _om ) = ran ( rec ( ( x e. _V |-> ( x +s 1s ) ) , C ) |` _om ) | 
						
							| 8 | 7 | eqcomi |  |-  ran ( rec ( ( x e. _V |-> ( x +s 1s ) ) , C ) |` _om ) = ( rec ( ( x e. _V |-> ( x +s 1s ) ) , C ) " _om ) | 
						
							| 9 | 2 | rneqd |  |-  ( ph -> ran G = ran ( rec ( ( x e. _V |-> ( x +s 1s ) ) , C ) |` _om ) ) | 
						
							| 10 | 8 9 3 | 3eqtr4a |  |-  ( ph -> ran G = Z ) | 
						
							| 11 |  | df-fo |  |-  ( G : _om -onto-> Z <-> ( G Fn _om /\ ran G = Z ) ) | 
						
							| 12 | 6 10 11 | sylanbrc |  |-  ( ph -> G : _om -onto-> Z ) |