| Step | Hyp | Ref | Expression | 
						
							| 1 |  | resscntz.p |  |-  H = ( G |`s A ) | 
						
							| 2 |  | resscntz.z |  |-  Z = ( Cntz ` G ) | 
						
							| 3 |  | resscntz.y |  |-  Y = ( Cntz ` H ) | 
						
							| 4 |  | eqid |  |-  ( Base ` H ) = ( Base ` H ) | 
						
							| 5 | 4 3 | cntzrcl |  |-  ( x e. ( Y ` S ) -> ( H e. _V /\ S C_ ( Base ` H ) ) ) | 
						
							| 6 | 5 | simprd |  |-  ( x e. ( Y ` S ) -> S C_ ( Base ` H ) ) | 
						
							| 7 |  | eqid |  |-  ( Base ` G ) = ( Base ` G ) | 
						
							| 8 | 1 7 | ressbasss |  |-  ( Base ` H ) C_ ( Base ` G ) | 
						
							| 9 | 6 8 | sstrdi |  |-  ( x e. ( Y ` S ) -> S C_ ( Base ` G ) ) | 
						
							| 10 | 9 | a1i |  |-  ( ( A e. V /\ S C_ A ) -> ( x e. ( Y ` S ) -> S C_ ( Base ` G ) ) ) | 
						
							| 11 |  | elinel1 |  |-  ( x e. ( ( Z ` S ) i^i A ) -> x e. ( Z ` S ) ) | 
						
							| 12 | 7 2 | cntzrcl |  |-  ( x e. ( Z ` S ) -> ( G e. _V /\ S C_ ( Base ` G ) ) ) | 
						
							| 13 | 12 | simprd |  |-  ( x e. ( Z ` S ) -> S C_ ( Base ` G ) ) | 
						
							| 14 | 11 13 | syl |  |-  ( x e. ( ( Z ` S ) i^i A ) -> S C_ ( Base ` G ) ) | 
						
							| 15 | 14 | a1i |  |-  ( ( A e. V /\ S C_ A ) -> ( x e. ( ( Z ` S ) i^i A ) -> S C_ ( Base ` G ) ) ) | 
						
							| 16 |  | elin |  |-  ( x e. ( A i^i ( Base ` G ) ) <-> ( x e. A /\ x e. ( Base ` G ) ) ) | 
						
							| 17 | 1 7 | ressbas |  |-  ( A e. V -> ( A i^i ( Base ` G ) ) = ( Base ` H ) ) | 
						
							| 18 | 17 | eleq2d |  |-  ( A e. V -> ( x e. ( A i^i ( Base ` G ) ) <-> x e. ( Base ` H ) ) ) | 
						
							| 19 | 16 18 | bitr3id |  |-  ( A e. V -> ( ( x e. A /\ x e. ( Base ` G ) ) <-> x e. ( Base ` H ) ) ) | 
						
							| 20 |  | eqid |  |-  ( +g ` G ) = ( +g ` G ) | 
						
							| 21 | 1 20 | ressplusg |  |-  ( A e. V -> ( +g ` G ) = ( +g ` H ) ) | 
						
							| 22 | 21 | oveqd |  |-  ( A e. V -> ( x ( +g ` G ) y ) = ( x ( +g ` H ) y ) ) | 
						
							| 23 | 21 | oveqd |  |-  ( A e. V -> ( y ( +g ` G ) x ) = ( y ( +g ` H ) x ) ) | 
						
							| 24 | 22 23 | eqeq12d |  |-  ( A e. V -> ( ( x ( +g ` G ) y ) = ( y ( +g ` G ) x ) <-> ( x ( +g ` H ) y ) = ( y ( +g ` H ) x ) ) ) | 
						
							| 25 | 24 | ralbidv |  |-  ( A e. V -> ( A. y e. S ( x ( +g ` G ) y ) = ( y ( +g ` G ) x ) <-> A. y e. S ( x ( +g ` H ) y ) = ( y ( +g ` H ) x ) ) ) | 
						
							| 26 | 19 25 | anbi12d |  |-  ( A e. V -> ( ( ( x e. A /\ x e. ( Base ` G ) ) /\ A. y e. S ( x ( +g ` G ) y ) = ( y ( +g ` G ) x ) ) <-> ( x e. ( Base ` H ) /\ A. y e. S ( x ( +g ` H ) y ) = ( y ( +g ` H ) x ) ) ) ) | 
						
							| 27 | 26 | ad2antrr |  |-  ( ( ( A e. V /\ S C_ A ) /\ S C_ ( Base ` G ) ) -> ( ( ( x e. A /\ x e. ( Base ` G ) ) /\ A. y e. S ( x ( +g ` G ) y ) = ( y ( +g ` G ) x ) ) <-> ( x e. ( Base ` H ) /\ A. y e. S ( x ( +g ` H ) y ) = ( y ( +g ` H ) x ) ) ) ) | 
						
							| 28 |  | anass |  |-  ( ( ( x e. A /\ x e. ( Base ` G ) ) /\ A. y e. S ( x ( +g ` G ) y ) = ( y ( +g ` G ) x ) ) <-> ( x e. A /\ ( x e. ( Base ` G ) /\ A. y e. S ( x ( +g ` G ) y ) = ( y ( +g ` G ) x ) ) ) ) | 
						
							| 29 | 27 28 | bitr3di |  |-  ( ( ( A e. V /\ S C_ A ) /\ S C_ ( Base ` G ) ) -> ( ( x e. ( Base ` H ) /\ A. y e. S ( x ( +g ` H ) y ) = ( y ( +g ` H ) x ) ) <-> ( x e. A /\ ( x e. ( Base ` G ) /\ A. y e. S ( x ( +g ` G ) y ) = ( y ( +g ` G ) x ) ) ) ) ) | 
						
							| 30 |  | ssin |  |-  ( ( S C_ A /\ S C_ ( Base ` G ) ) <-> S C_ ( A i^i ( Base ` G ) ) ) | 
						
							| 31 | 17 | sseq2d |  |-  ( A e. V -> ( S C_ ( A i^i ( Base ` G ) ) <-> S C_ ( Base ` H ) ) ) | 
						
							| 32 | 30 31 | bitrid |  |-  ( A e. V -> ( ( S C_ A /\ S C_ ( Base ` G ) ) <-> S C_ ( Base ` H ) ) ) | 
						
							| 33 | 32 | biimpd |  |-  ( A e. V -> ( ( S C_ A /\ S C_ ( Base ` G ) ) -> S C_ ( Base ` H ) ) ) | 
						
							| 34 | 33 | impl |  |-  ( ( ( A e. V /\ S C_ A ) /\ S C_ ( Base ` G ) ) -> S C_ ( Base ` H ) ) | 
						
							| 35 |  | eqid |  |-  ( +g ` H ) = ( +g ` H ) | 
						
							| 36 | 4 35 3 | elcntz |  |-  ( S C_ ( Base ` H ) -> ( x e. ( Y ` S ) <-> ( x e. ( Base ` H ) /\ A. y e. S ( x ( +g ` H ) y ) = ( y ( +g ` H ) x ) ) ) ) | 
						
							| 37 | 34 36 | syl |  |-  ( ( ( A e. V /\ S C_ A ) /\ S C_ ( Base ` G ) ) -> ( x e. ( Y ` S ) <-> ( x e. ( Base ` H ) /\ A. y e. S ( x ( +g ` H ) y ) = ( y ( +g ` H ) x ) ) ) ) | 
						
							| 38 |  | elin |  |-  ( x e. ( ( Z ` S ) i^i A ) <-> ( x e. ( Z ` S ) /\ x e. A ) ) | 
						
							| 39 | 38 | biancomi |  |-  ( x e. ( ( Z ` S ) i^i A ) <-> ( x e. A /\ x e. ( Z ` S ) ) ) | 
						
							| 40 | 7 20 2 | elcntz |  |-  ( S C_ ( Base ` G ) -> ( x e. ( Z ` S ) <-> ( x e. ( Base ` G ) /\ A. y e. S ( x ( +g ` G ) y ) = ( y ( +g ` G ) x ) ) ) ) | 
						
							| 41 | 40 | adantl |  |-  ( ( ( A e. V /\ S C_ A ) /\ S C_ ( Base ` G ) ) -> ( x e. ( Z ` S ) <-> ( x e. ( Base ` G ) /\ A. y e. S ( x ( +g ` G ) y ) = ( y ( +g ` G ) x ) ) ) ) | 
						
							| 42 | 41 | anbi2d |  |-  ( ( ( A e. V /\ S C_ A ) /\ S C_ ( Base ` G ) ) -> ( ( x e. A /\ x e. ( Z ` S ) ) <-> ( x e. A /\ ( x e. ( Base ` G ) /\ A. y e. S ( x ( +g ` G ) y ) = ( y ( +g ` G ) x ) ) ) ) ) | 
						
							| 43 | 39 42 | bitrid |  |-  ( ( ( A e. V /\ S C_ A ) /\ S C_ ( Base ` G ) ) -> ( x e. ( ( Z ` S ) i^i A ) <-> ( x e. A /\ ( x e. ( Base ` G ) /\ A. y e. S ( x ( +g ` G ) y ) = ( y ( +g ` G ) x ) ) ) ) ) | 
						
							| 44 | 29 37 43 | 3bitr4d |  |-  ( ( ( A e. V /\ S C_ A ) /\ S C_ ( Base ` G ) ) -> ( x e. ( Y ` S ) <-> x e. ( ( Z ` S ) i^i A ) ) ) | 
						
							| 45 | 44 | ex |  |-  ( ( A e. V /\ S C_ A ) -> ( S C_ ( Base ` G ) -> ( x e. ( Y ` S ) <-> x e. ( ( Z ` S ) i^i A ) ) ) ) | 
						
							| 46 | 10 15 45 | pm5.21ndd |  |-  ( ( A e. V /\ S C_ A ) -> ( x e. ( Y ` S ) <-> x e. ( ( Z ` S ) i^i A ) ) ) | 
						
							| 47 | 46 | eqrdv |  |-  ( ( A e. V /\ S C_ A ) -> ( Y ` S ) = ( ( Z ` S ) i^i A ) ) |