| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							bnj1312.1 | 
							 |-  B = { d | ( d C_ A /\ A. x e. d _pred ( x , A , R ) C_ d ) } | 
						
						
							| 2 | 
							
								
							 | 
							bnj1312.2 | 
							 |-  Y = <. x , ( f |` _pred ( x , A , R ) ) >.  | 
						
						
							| 3 | 
							
								
							 | 
							bnj1312.3 | 
							 |-  C = { f | E. d e. B ( f Fn d /\ A. x e. d ( f ` x ) = ( G ` Y ) ) } | 
						
						
							| 4 | 
							
								
							 | 
							bnj1312.4 | 
							 |-  ( ta <-> ( f e. C /\ dom f = ( { x } u. _trCl ( x , A , R ) ) ) ) | 
						
						
							| 5 | 
							
								
							 | 
							bnj1312.5 | 
							 |-  D = { x e. A | -. E. f ta } | 
						
						
							| 6 | 
							
								
							 | 
							bnj1312.6 | 
							 |-  ( ps <-> ( R _FrSe A /\ D =/= (/) ) )  | 
						
						
							| 7 | 
							
								
							 | 
							bnj1312.7 | 
							 |-  ( ch <-> ( ps /\ x e. D /\ A. y e. D -. y R x ) )  | 
						
						
							| 8 | 
							
								
							 | 
							bnj1312.8 | 
							 |-  ( ta' <-> [. y / x ]. ta )  | 
						
						
							| 9 | 
							
								
							 | 
							bnj1312.9 | 
							 |-  H = { f | E. y e. _pred ( x , A , R ) ta' } | 
						
						
							| 10 | 
							
								
							 | 
							bnj1312.10 | 
							 |-  P = U. H  | 
						
						
							| 11 | 
							
								
							 | 
							bnj1312.11 | 
							 |-  Z = <. x , ( P |` _pred ( x , A , R ) ) >.  | 
						
						
							| 12 | 
							
								
							 | 
							bnj1312.12 | 
							 |-  Q = ( P u. { <. x , ( G ` Z ) >. } ) | 
						
						
							| 13 | 
							
								
							 | 
							bnj1312.13 | 
							 |-  W = <. z , ( Q |` _pred ( z , A , R ) ) >.  | 
						
						
							| 14 | 
							
								
							 | 
							bnj1312.14 | 
							 |-  E = ( { x } u. _trCl ( x , A , R ) ) | 
						
						
							| 15 | 
							
								6
							 | 
							simplbi | 
							 |-  ( ps -> R _FrSe A )  | 
						
						
							| 16 | 
							
								5
							 | 
							ssrab3 | 
							 |-  D C_ A  | 
						
						
							| 17 | 
							
								16
							 | 
							a1i | 
							 |-  ( ps -> D C_ A )  | 
						
						
							| 18 | 
							
								6
							 | 
							simprbi | 
							 |-  ( ps -> D =/= (/) )  | 
						
						
							| 19 | 
							
								5
							 | 
							bnj1230 | 
							 |-  ( w e. D -> A. x w e. D )  | 
						
						
							| 20 | 
							
								19
							 | 
							bnj1228 | 
							 |-  ( ( R _FrSe A /\ D C_ A /\ D =/= (/) ) -> E. x e. D A. y e. D -. y R x )  | 
						
						
							| 21 | 
							
								15 17 18 20
							 | 
							syl3anc | 
							 |-  ( ps -> E. x e. D A. y e. D -. y R x )  | 
						
						
							| 22 | 
							
								
							 | 
							nfv | 
							 |-  F/ x R _FrSe A  | 
						
						
							| 23 | 
							
								19
							 | 
							nfcii | 
							 |-  F/_ x D  | 
						
						
							| 24 | 
							
								
							 | 
							nfcv | 
							 |-  F/_ x (/)  | 
						
						
							| 25 | 
							
								23 24
							 | 
							nfne | 
							 |-  F/ x D =/= (/)  | 
						
						
							| 26 | 
							
								22 25
							 | 
							nfan | 
							 |-  F/ x ( R _FrSe A /\ D =/= (/) )  | 
						
						
							| 27 | 
							
								6 26
							 | 
							nfxfr | 
							 |-  F/ x ps  | 
						
						
							| 28 | 
							
								27
							 | 
							nf5ri | 
							 |-  ( ps -> A. x ps )  | 
						
						
							| 29 | 
							
								21 7 28
							 | 
							bnj1521 | 
							 |-  ( ps -> E. x ch )  | 
						
						
							| 30 | 
							
								7
							 | 
							simp2bi | 
							 |-  ( ch -> x e. D )  | 
						
						
							| 31 | 
							
								5
							 | 
							bnj1538 | 
							 |-  ( x e. D -> -. E. f ta )  | 
						
						
							| 32 | 
							
								1 2 3 4 5 6 7 8 9 10 11 12
							 | 
							bnj1489 | 
							 |-  ( ch -> Q e. _V )  | 
						
						
							| 33 | 
							
								7 15
							 | 
							bnj835 | 
							 |-  ( ch -> R _FrSe A )  | 
						
						
							| 34 | 
							
								1 2 3 4 5 6 7 8 9 10
							 | 
							bnj1384 | 
							 |-  ( R _FrSe A -> Fun P )  | 
						
						
							| 35 | 
							
								33 34
							 | 
							syl | 
							 |-  ( ch -> Fun P )  | 
						
						
							| 36 | 
							
								1 2 3 4 5 6 7 8 9 10
							 | 
							bnj1415 | 
							 |-  ( ch -> dom P = _trCl ( x , A , R ) )  | 
						
						
							| 37 | 
							
								35 36
							 | 
							bnj1422 | 
							 |-  ( ch -> P Fn _trCl ( x , A , R ) )  | 
						
						
							| 38 | 
							
								1 2 3 4 5 6 7 8 9 10 11 12 36
							 | 
							bnj1416 | 
							 |-  ( ch -> dom Q = ( { x } u. _trCl ( x , A , R ) ) ) | 
						
						
							| 39 | 
							
								1 2 3 4 5 6 7 8 9 10 11 12 35 38 36
							 | 
							bnj1421 | 
							 |-  ( ch -> Fun Q )  | 
						
						
							| 40 | 
							
								39 38
							 | 
							bnj1422 | 
							 |-  ( ch -> Q Fn ( { x } u. _trCl ( x , A , R ) ) ) | 
						
						
							| 41 | 
							
								1 2 3 4 5 6 7 8 9 10 11 12 13 14 37 40
							 | 
							bnj1423 | 
							 |-  ( ch -> A. z e. E ( Q ` z ) = ( G ` W ) )  | 
						
						
							| 42 | 
							
								14
							 | 
							fneq2i | 
							 |-  ( Q Fn E <-> Q Fn ( { x } u. _trCl ( x , A , R ) ) ) | 
						
						
							| 43 | 
							
								40 42
							 | 
							sylibr | 
							 |-  ( ch -> Q Fn E )  | 
						
						
							| 44 | 
							
								1 2 3 4 5 6 7 8 9 10 11 12 13 14
							 | 
							bnj1452 | 
							 |-  ( ch -> E e. B )  | 
						
						
							| 45 | 
							
								1 2 3 4 5 6 7 8 9 10 11 12 13 14 32 41 43 44
							 | 
							bnj1463 | 
							 |-  ( ch -> Q e. C )  | 
						
						
							| 46 | 
							
								45 38
							 | 
							jca | 
							 |-  ( ch -> ( Q e. C /\ dom Q = ( { x } u. _trCl ( x , A , R ) ) ) ) | 
						
						
							| 47 | 
							
								1 2 3 4 5 6 7 8 9 10 11 12 46
							 | 
							bnj1491 | 
							 |-  ( ( ch /\ Q e. _V ) -> E. f ( f e. C /\ dom f = ( { x } u. _trCl ( x , A , R ) ) ) ) | 
						
						
							| 48 | 
							
								32 47
							 | 
							mpdan | 
							 |-  ( ch -> E. f ( f e. C /\ dom f = ( { x } u. _trCl ( x , A , R ) ) ) ) | 
						
						
							| 49 | 
							
								48 4
							 | 
							bnj1198 | 
							 |-  ( ch -> E. f ta )  | 
						
						
							| 50 | 
							
								31 49
							 | 
							nsyl3 | 
							 |-  ( ch -> -. x e. D )  | 
						
						
							| 51 | 
							
								29 30 50
							 | 
							bnj1304 | 
							 |-  -. ps  | 
						
						
							| 52 | 
							
								6 51
							 | 
							bnj1541 | 
							 |-  ( R _FrSe A -> D = (/) )  | 
						
						
							| 53 | 
							
								5 52
							 | 
							bnj1476 | 
							 |-  ( R _FrSe A -> A. x e. A E. f ta )  | 
						
						
							| 54 | 
							
								4
							 | 
							exbii | 
							 |-  ( E. f ta <-> E. f ( f e. C /\ dom f = ( { x } u. _trCl ( x , A , R ) ) ) ) | 
						
						
							| 55 | 
							
								
							 | 
							df-rex | 
							 |-  ( E. f e. C dom f = ( { x } u. _trCl ( x , A , R ) ) <-> E. f ( f e. C /\ dom f = ( { x } u. _trCl ( x , A , R ) ) ) ) | 
						
						
							| 56 | 
							
								54 55
							 | 
							bitr4i | 
							 |-  ( E. f ta <-> E. f e. C dom f = ( { x } u. _trCl ( x , A , R ) ) ) | 
						
						
							| 57 | 
							
								56
							 | 
							ralbii | 
							 |-  ( A. x e. A E. f ta <-> A. x e. A E. f e. C dom f = ( { x } u. _trCl ( x , A , R ) ) ) | 
						
						
							| 58 | 
							
								53 57
							 | 
							sylib | 
							 |-  ( R _FrSe A -> A. x e. A E. f e. C dom f = ( { x } u. _trCl ( x , A , R ) ) ) |