| Step | Hyp | Ref | Expression | 
						
							| 1 |  | konigth.1 |  |-  A e. _V | 
						
							| 2 |  | konigth.2 |  |-  S = U_ i e. A ( M ` i ) | 
						
							| 3 |  | konigth.3 |  |-  P = X_ i e. A ( N ` i ) | 
						
							| 4 |  | konigth.4 |  |-  D = ( i e. A |-> ( a e. ( M ` i ) |-> ( ( f ` a ) ` i ) ) ) | 
						
							| 5 |  | konigth.5 |  |-  E = ( i e. A |-> ( e ` i ) ) | 
						
							| 6 |  | fvex |  |-  ( M ` i ) e. _V | 
						
							| 7 |  | fvex |  |-  ( ( f ` a ) ` i ) e. _V | 
						
							| 8 |  | eqid |  |-  ( a e. ( M ` i ) |-> ( ( f ` a ) ` i ) ) = ( a e. ( M ` i ) |-> ( ( f ` a ) ` i ) ) | 
						
							| 9 | 7 8 | fnmpti |  |-  ( a e. ( M ` i ) |-> ( ( f ` a ) ` i ) ) Fn ( M ` i ) | 
						
							| 10 | 6 | mptex |  |-  ( a e. ( M ` i ) |-> ( ( f ` a ) ` i ) ) e. _V | 
						
							| 11 | 4 | fvmpt2 |  |-  ( ( i e. A /\ ( a e. ( M ` i ) |-> ( ( f ` a ) ` i ) ) e. _V ) -> ( D ` i ) = ( a e. ( M ` i ) |-> ( ( f ` a ) ` i ) ) ) | 
						
							| 12 | 10 11 | mpan2 |  |-  ( i e. A -> ( D ` i ) = ( a e. ( M ` i ) |-> ( ( f ` a ) ` i ) ) ) | 
						
							| 13 | 12 | fneq1d |  |-  ( i e. A -> ( ( D ` i ) Fn ( M ` i ) <-> ( a e. ( M ` i ) |-> ( ( f ` a ) ` i ) ) Fn ( M ` i ) ) ) | 
						
							| 14 | 9 13 | mpbiri |  |-  ( i e. A -> ( D ` i ) Fn ( M ` i ) ) | 
						
							| 15 |  | fnrndomg |  |-  ( ( M ` i ) e. _V -> ( ( D ` i ) Fn ( M ` i ) -> ran ( D ` i ) ~<_ ( M ` i ) ) ) | 
						
							| 16 | 6 14 15 | mpsyl |  |-  ( i e. A -> ran ( D ` i ) ~<_ ( M ` i ) ) | 
						
							| 17 |  | domsdomtr |  |-  ( ( ran ( D ` i ) ~<_ ( M ` i ) /\ ( M ` i ) ~< ( N ` i ) ) -> ran ( D ` i ) ~< ( N ` i ) ) | 
						
							| 18 | 16 17 | sylan |  |-  ( ( i e. A /\ ( M ` i ) ~< ( N ` i ) ) -> ran ( D ` i ) ~< ( N ` i ) ) | 
						
							| 19 |  | sdomdif |  |-  ( ran ( D ` i ) ~< ( N ` i ) -> ( ( N ` i ) \ ran ( D ` i ) ) =/= (/) ) | 
						
							| 20 | 18 19 | syl |  |-  ( ( i e. A /\ ( M ` i ) ~< ( N ` i ) ) -> ( ( N ` i ) \ ran ( D ` i ) ) =/= (/) ) | 
						
							| 21 | 20 | ralimiaa |  |-  ( A. i e. A ( M ` i ) ~< ( N ` i ) -> A. i e. A ( ( N ` i ) \ ran ( D ` i ) ) =/= (/) ) | 
						
							| 22 |  | fvex |  |-  ( N ` i ) e. _V | 
						
							| 23 | 22 | difexi |  |-  ( ( N ` i ) \ ran ( D ` i ) ) e. _V | 
						
							| 24 | 1 23 | ac6c5 |  |-  ( A. i e. A ( ( N ` i ) \ ran ( D ` i ) ) =/= (/) -> E. e A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) ) | 
						
							| 25 |  | equid |  |-  f = f | 
						
							| 26 |  | eldifi |  |-  ( ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> ( e ` i ) e. ( N ` i ) ) | 
						
							| 27 |  | fvex |  |-  ( e ` i ) e. _V | 
						
							| 28 | 5 | fvmpt2 |  |-  ( ( i e. A /\ ( e ` i ) e. _V ) -> ( E ` i ) = ( e ` i ) ) | 
						
							| 29 | 27 28 | mpan2 |  |-  ( i e. A -> ( E ` i ) = ( e ` i ) ) | 
						
							| 30 | 29 | eleq1d |  |-  ( i e. A -> ( ( E ` i ) e. ( N ` i ) <-> ( e ` i ) e. ( N ` i ) ) ) | 
						
							| 31 | 26 30 | imbitrrid |  |-  ( i e. A -> ( ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> ( E ` i ) e. ( N ` i ) ) ) | 
						
							| 32 | 31 | ralimia |  |-  ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> A. i e. A ( E ` i ) e. ( N ` i ) ) | 
						
							| 33 | 27 5 | fnmpti |  |-  E Fn A | 
						
							| 34 | 32 33 | jctil |  |-  ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> ( E Fn A /\ A. i e. A ( E ` i ) e. ( N ` i ) ) ) | 
						
							| 35 | 1 | mptex |  |-  ( i e. A |-> ( e ` i ) ) e. _V | 
						
							| 36 | 5 35 | eqeltri |  |-  E e. _V | 
						
							| 37 | 36 | elixp |  |-  ( E e. X_ i e. A ( N ` i ) <-> ( E Fn A /\ A. i e. A ( E ` i ) e. ( N ` i ) ) ) | 
						
							| 38 | 34 37 | sylibr |  |-  ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> E e. X_ i e. A ( N ` i ) ) | 
						
							| 39 | 38 3 | eleqtrrdi |  |-  ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> E e. P ) | 
						
							| 40 |  | foelrn |  |-  ( ( f : S -onto-> P /\ E e. P ) -> E. a e. S E = ( f ` a ) ) | 
						
							| 41 | 40 | expcom |  |-  ( E e. P -> ( f : S -onto-> P -> E. a e. S E = ( f ` a ) ) ) | 
						
							| 42 | 2 | eleq2i |  |-  ( a e. S <-> a e. U_ i e. A ( M ` i ) ) | 
						
							| 43 |  | eliun |  |-  ( a e. U_ i e. A ( M ` i ) <-> E. i e. A a e. ( M ` i ) ) | 
						
							| 44 | 42 43 | bitri |  |-  ( a e. S <-> E. i e. A a e. ( M ` i ) ) | 
						
							| 45 |  | nfra1 |  |-  F/ i A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) | 
						
							| 46 |  | nfv |  |-  F/ i E = ( f ` a ) | 
						
							| 47 | 45 46 | nfan |  |-  F/ i ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) /\ E = ( f ` a ) ) | 
						
							| 48 |  | nfv |  |-  F/ i -. f = f | 
						
							| 49 | 29 | ad2antrl |  |-  ( ( E = ( f ` a ) /\ ( i e. A /\ a e. ( M ` i ) ) ) -> ( E ` i ) = ( e ` i ) ) | 
						
							| 50 |  | fveq1 |  |-  ( E = ( f ` a ) -> ( E ` i ) = ( ( f ` a ) ` i ) ) | 
						
							| 51 | 12 | fveq1d |  |-  ( i e. A -> ( ( D ` i ) ` a ) = ( ( a e. ( M ` i ) |-> ( ( f ` a ) ` i ) ) ` a ) ) | 
						
							| 52 | 8 | fvmpt2 |  |-  ( ( a e. ( M ` i ) /\ ( ( f ` a ) ` i ) e. _V ) -> ( ( a e. ( M ` i ) |-> ( ( f ` a ) ` i ) ) ` a ) = ( ( f ` a ) ` i ) ) | 
						
							| 53 | 7 52 | mpan2 |  |-  ( a e. ( M ` i ) -> ( ( a e. ( M ` i ) |-> ( ( f ` a ) ` i ) ) ` a ) = ( ( f ` a ) ` i ) ) | 
						
							| 54 | 51 53 | sylan9eq |  |-  ( ( i e. A /\ a e. ( M ` i ) ) -> ( ( D ` i ) ` a ) = ( ( f ` a ) ` i ) ) | 
						
							| 55 | 54 | eqcomd |  |-  ( ( i e. A /\ a e. ( M ` i ) ) -> ( ( f ` a ) ` i ) = ( ( D ` i ) ` a ) ) | 
						
							| 56 | 50 55 | sylan9eq |  |-  ( ( E = ( f ` a ) /\ ( i e. A /\ a e. ( M ` i ) ) ) -> ( E ` i ) = ( ( D ` i ) ` a ) ) | 
						
							| 57 | 49 56 | eqtr3d |  |-  ( ( E = ( f ` a ) /\ ( i e. A /\ a e. ( M ` i ) ) ) -> ( e ` i ) = ( ( D ` i ) ` a ) ) | 
						
							| 58 |  | fnfvelrn |  |-  ( ( ( D ` i ) Fn ( M ` i ) /\ a e. ( M ` i ) ) -> ( ( D ` i ) ` a ) e. ran ( D ` i ) ) | 
						
							| 59 | 14 58 | sylan |  |-  ( ( i e. A /\ a e. ( M ` i ) ) -> ( ( D ` i ) ` a ) e. ran ( D ` i ) ) | 
						
							| 60 | 59 | adantl |  |-  ( ( E = ( f ` a ) /\ ( i e. A /\ a e. ( M ` i ) ) ) -> ( ( D ` i ) ` a ) e. ran ( D ` i ) ) | 
						
							| 61 | 57 60 | eqeltrd |  |-  ( ( E = ( f ` a ) /\ ( i e. A /\ a e. ( M ` i ) ) ) -> ( e ` i ) e. ran ( D ` i ) ) | 
						
							| 62 | 61 | 3adant1 |  |-  ( ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) /\ E = ( f ` a ) /\ ( i e. A /\ a e. ( M ` i ) ) ) -> ( e ` i ) e. ran ( D ` i ) ) | 
						
							| 63 |  | simp1 |  |-  ( ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) /\ E = ( f ` a ) /\ ( i e. A /\ a e. ( M ` i ) ) ) -> A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) ) | 
						
							| 64 |  | simp3l |  |-  ( ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) /\ E = ( f ` a ) /\ ( i e. A /\ a e. ( M ` i ) ) ) -> i e. A ) | 
						
							| 65 |  | rsp |  |-  ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> ( i e. A -> ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) ) ) | 
						
							| 66 |  | eldifn |  |-  ( ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> -. ( e ` i ) e. ran ( D ` i ) ) | 
						
							| 67 | 65 66 | syl6 |  |-  ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> ( i e. A -> -. ( e ` i ) e. ran ( D ` i ) ) ) | 
						
							| 68 | 63 64 67 | sylc |  |-  ( ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) /\ E = ( f ` a ) /\ ( i e. A /\ a e. ( M ` i ) ) ) -> -. ( e ` i ) e. ran ( D ` i ) ) | 
						
							| 69 | 62 68 | pm2.21dd |  |-  ( ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) /\ E = ( f ` a ) /\ ( i e. A /\ a e. ( M ` i ) ) ) -> -. f = f ) | 
						
							| 70 | 69 | 3expia |  |-  ( ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) /\ E = ( f ` a ) ) -> ( ( i e. A /\ a e. ( M ` i ) ) -> -. f = f ) ) | 
						
							| 71 | 70 | expd |  |-  ( ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) /\ E = ( f ` a ) ) -> ( i e. A -> ( a e. ( M ` i ) -> -. f = f ) ) ) | 
						
							| 72 | 47 48 71 | rexlimd |  |-  ( ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) /\ E = ( f ` a ) ) -> ( E. i e. A a e. ( M ` i ) -> -. f = f ) ) | 
						
							| 73 | 44 72 | biimtrid |  |-  ( ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) /\ E = ( f ` a ) ) -> ( a e. S -> -. f = f ) ) | 
						
							| 74 | 73 | ex |  |-  ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> ( E = ( f ` a ) -> ( a e. S -> -. f = f ) ) ) | 
						
							| 75 | 74 | com23 |  |-  ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> ( a e. S -> ( E = ( f ` a ) -> -. f = f ) ) ) | 
						
							| 76 | 75 | rexlimdv |  |-  ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> ( E. a e. S E = ( f ` a ) -> -. f = f ) ) | 
						
							| 77 | 41 76 | syl9r |  |-  ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> ( E e. P -> ( f : S -onto-> P -> -. f = f ) ) ) | 
						
							| 78 | 39 77 | mpd |  |-  ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> ( f : S -onto-> P -> -. f = f ) ) | 
						
							| 79 | 25 78 | mt2i |  |-  ( A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> -. f : S -onto-> P ) | 
						
							| 80 | 79 | exlimiv |  |-  ( E. e A. i e. A ( e ` i ) e. ( ( N ` i ) \ ran ( D ` i ) ) -> -. f : S -onto-> P ) | 
						
							| 81 | 21 24 80 | 3syl |  |-  ( A. i e. A ( M ` i ) ~< ( N ` i ) -> -. f : S -onto-> P ) | 
						
							| 82 | 81 | nexdv |  |-  ( A. i e. A ( M ` i ) ~< ( N ` i ) -> -. E. f f : S -onto-> P ) | 
						
							| 83 | 6 | 0dom |  |-  (/) ~<_ ( M ` i ) | 
						
							| 84 |  | domsdomtr |  |-  ( ( (/) ~<_ ( M ` i ) /\ ( M ` i ) ~< ( N ` i ) ) -> (/) ~< ( N ` i ) ) | 
						
							| 85 | 83 84 | mpan |  |-  ( ( M ` i ) ~< ( N ` i ) -> (/) ~< ( N ` i ) ) | 
						
							| 86 | 22 | 0sdom |  |-  ( (/) ~< ( N ` i ) <-> ( N ` i ) =/= (/) ) | 
						
							| 87 | 85 86 | sylib |  |-  ( ( M ` i ) ~< ( N ` i ) -> ( N ` i ) =/= (/) ) | 
						
							| 88 | 87 | ralimi |  |-  ( A. i e. A ( M ` i ) ~< ( N ` i ) -> A. i e. A ( N ` i ) =/= (/) ) | 
						
							| 89 | 3 | neeq1i |  |-  ( P =/= (/) <-> X_ i e. A ( N ` i ) =/= (/) ) | 
						
							| 90 | 22 | rgenw |  |-  A. i e. A ( N ` i ) e. _V | 
						
							| 91 |  | ixpexg |  |-  ( A. i e. A ( N ` i ) e. _V -> X_ i e. A ( N ` i ) e. _V ) | 
						
							| 92 | 90 91 | ax-mp |  |-  X_ i e. A ( N ` i ) e. _V | 
						
							| 93 | 3 92 | eqeltri |  |-  P e. _V | 
						
							| 94 | 93 | 0sdom |  |-  ( (/) ~< P <-> P =/= (/) ) | 
						
							| 95 | 1 22 | ac9 |  |-  ( A. i e. A ( N ` i ) =/= (/) <-> X_ i e. A ( N ` i ) =/= (/) ) | 
						
							| 96 | 89 94 95 | 3bitr4i |  |-  ( (/) ~< P <-> A. i e. A ( N ` i ) =/= (/) ) | 
						
							| 97 | 88 96 | sylibr |  |-  ( A. i e. A ( M ` i ) ~< ( N ` i ) -> (/) ~< P ) | 
						
							| 98 | 1 6 | iunex |  |-  U_ i e. A ( M ` i ) e. _V | 
						
							| 99 | 2 98 | eqeltri |  |-  S e. _V | 
						
							| 100 |  | domtri |  |-  ( ( P e. _V /\ S e. _V ) -> ( P ~<_ S <-> -. S ~< P ) ) | 
						
							| 101 | 93 99 100 | mp2an |  |-  ( P ~<_ S <-> -. S ~< P ) | 
						
							| 102 | 101 | biimpri |  |-  ( -. S ~< P -> P ~<_ S ) | 
						
							| 103 |  | fodomr |  |-  ( ( (/) ~< P /\ P ~<_ S ) -> E. f f : S -onto-> P ) | 
						
							| 104 | 97 102 103 | syl2an |  |-  ( ( A. i e. A ( M ` i ) ~< ( N ` i ) /\ -. S ~< P ) -> E. f f : S -onto-> P ) | 
						
							| 105 | 82 104 | mtand |  |-  ( A. i e. A ( M ` i ) ~< ( N ` i ) -> -. -. S ~< P ) | 
						
							| 106 | 105 | notnotrd |  |-  ( A. i e. A ( M ` i ) ~< ( N ` i ) -> S ~< P ) |