| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							bnj907.1 | 
							 |-  ( ph <-> ( f ` (/) ) = _pred ( X , A , R ) )  | 
						
						
							| 2 | 
							
								
							 | 
							bnj907.2 | 
							 |-  ( ps <-> A. i e. _om ( suc i e. n -> ( f ` suc i ) = U_ y e. ( f ` i ) _pred ( y , A , R ) ) )  | 
						
						
							| 3 | 
							
								
							 | 
							bnj907.3 | 
							 |-  ( ch <-> ( n e. D /\ f Fn n /\ ph /\ ps ) )  | 
						
						
							| 4 | 
							
								
							 | 
							bnj907.4 | 
							 |-  ( th <-> ( R _FrSe A /\ X e. A /\ y e. _trCl ( X , A , R ) /\ z e. _pred ( y , A , R ) ) )  | 
						
						
							| 5 | 
							
								
							 | 
							bnj907.5 | 
							 |-  ( ta <-> ( m e. _om /\ n = suc m /\ p = suc n ) )  | 
						
						
							| 6 | 
							
								
							 | 
							bnj907.6 | 
							 |-  ( et <-> ( i e. n /\ y e. ( f ` i ) ) )  | 
						
						
							| 7 | 
							
								
							 | 
							bnj907.7 | 
							 |-  ( ph' <-> [. p / n ]. ph )  | 
						
						
							| 8 | 
							
								
							 | 
							bnj907.8 | 
							 |-  ( ps' <-> [. p / n ]. ps )  | 
						
						
							| 9 | 
							
								
							 | 
							bnj907.9 | 
							 |-  ( ch' <-> [. p / n ]. ch )  | 
						
						
							| 10 | 
							
								
							 | 
							bnj907.10 | 
							 |-  ( ph" <-> [. G / f ]. ph' )  | 
						
						
							| 11 | 
							
								
							 | 
							bnj907.11 | 
							 |-  ( ps" <-> [. G / f ]. ps' )  | 
						
						
							| 12 | 
							
								
							 | 
							bnj907.12 | 
							 |-  ( ch" <-> [. G / f ]. ch' )  | 
						
						
							| 13 | 
							
								
							 | 
							bnj907.13 | 
							 |-  D = ( _om \ { (/) } ) | 
						
						
							| 14 | 
							
								
							 | 
							bnj907.14 | 
							 |-  B = { f | E. n e. D ( f Fn n /\ ph /\ ps ) } | 
						
						
							| 15 | 
							
								
							 | 
							bnj907.15 | 
							 |-  C = U_ y e. ( f ` m ) _pred ( y , A , R )  | 
						
						
							| 16 | 
							
								
							 | 
							bnj907.16 | 
							 |-  G = ( f u. { <. n , C >. } ) | 
						
						
							| 17 | 
							
								1 2 3 4 5 6 13 14
							 | 
							bnj1021 | 
							 |-  E. f E. n E. i E. m ( th -> ( th /\ ch /\ et /\ E. p ta ) )  | 
						
						
							| 18 | 
							
								
							 | 
							vex | 
							 |-  p e. _V  | 
						
						
							| 19 | 
							
								3 7 8 9 18
							 | 
							bnj919 | 
							 |-  ( ch' <-> ( p e. D /\ f Fn p /\ ph' /\ ps' ) )  | 
						
						
							| 20 | 
							
								16
							 | 
							bnj918 | 
							 |-  G e. _V  | 
						
						
							| 21 | 
							
								19 10 11 12 20
							 | 
							bnj976 | 
							 |-  ( ch" <-> ( p e. D /\ G Fn p /\ ph" /\ ps" ) )  | 
						
						
							| 22 | 
							
								1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 21
							 | 
							bnj1020 | 
							 |-  ( ( th /\ ch /\ et /\ E. p ta ) -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) )  | 
						
						
							| 23 | 
							
								22
							 | 
							ax-gen | 
							 |-  A. m ( ( th /\ ch /\ et /\ E. p ta ) -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) )  | 
						
						
							| 24 | 
							
								
							 | 
							19.29r | 
							 |-  ( ( E. m ( th -> ( th /\ ch /\ et /\ E. p ta ) ) /\ A. m ( ( th /\ ch /\ et /\ E. p ta ) -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) ) -> E. m ( ( th -> ( th /\ ch /\ et /\ E. p ta ) ) /\ ( ( th /\ ch /\ et /\ E. p ta ) -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) ) )  | 
						
						
							| 25 | 
							
								
							 | 
							pm3.33 | 
							 |-  ( ( ( th -> ( th /\ ch /\ et /\ E. p ta ) ) /\ ( ( th /\ ch /\ et /\ E. p ta ) -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) ) -> ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) )  | 
						
						
							| 26 | 
							
								24 25
							 | 
							bnj593 | 
							 |-  ( ( E. m ( th -> ( th /\ ch /\ et /\ E. p ta ) ) /\ A. m ( ( th /\ ch /\ et /\ E. p ta ) -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) ) -> E. m ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) )  | 
						
						
							| 27 | 
							
								23 26
							 | 
							mpan2 | 
							 |-  ( E. m ( th -> ( th /\ ch /\ et /\ E. p ta ) ) -> E. m ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) )  | 
						
						
							| 28 | 
							
								27
							 | 
							2eximi | 
							 |-  ( E. n E. i E. m ( th -> ( th /\ ch /\ et /\ E. p ta ) ) -> E. n E. i E. m ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) )  | 
						
						
							| 29 | 
							
								17 28
							 | 
							bnj101 | 
							 |-  E. f E. n E. i E. m ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) )  | 
						
						
							| 30 | 
							
								
							 | 
							19.9v | 
							 |-  ( E. f E. n E. i E. m ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) <-> E. n E. i E. m ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) )  | 
						
						
							| 31 | 
							
								29 30
							 | 
							mpbi | 
							 |-  E. n E. i E. m ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) )  | 
						
						
							| 32 | 
							
								
							 | 
							19.9v | 
							 |-  ( E. n E. i E. m ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) <-> E. i E. m ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) )  | 
						
						
							| 33 | 
							
								31 32
							 | 
							mpbi | 
							 |-  E. i E. m ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) )  | 
						
						
							| 34 | 
							
								
							 | 
							19.9v | 
							 |-  ( E. i E. m ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) <-> E. m ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) )  | 
						
						
							| 35 | 
							
								33 34
							 | 
							mpbi | 
							 |-  E. m ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) )  | 
						
						
							| 36 | 
							
								
							 | 
							19.9v | 
							 |-  ( E. m ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) <-> ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) ) )  | 
						
						
							| 37 | 
							
								35 36
							 | 
							mpbi | 
							 |-  ( th -> _pred ( y , A , R ) C_ _trCl ( X , A , R ) )  | 
						
						
							| 38 | 
							
								4
							 | 
							bnj1254 | 
							 |-  ( th -> z e. _pred ( y , A , R ) )  | 
						
						
							| 39 | 
							
								37 38
							 | 
							sseldd | 
							 |-  ( th -> z e. _trCl ( X , A , R ) )  | 
						
						
							| 40 | 
							
								4 39
							 | 
							bnj978 | 
							 |-  ( ( R _FrSe A /\ X e. A ) -> _TrFo ( _trCl ( X , A , R ) , A , R ) )  |