| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ackbij.f |  |-  F = ( x e. ( ~P _om i^i Fin ) |-> ( card ` U_ y e. x ( { y } X. ~P y ) ) ) | 
						
							| 2 |  | difss |  |-  ( A \ |^| ( _om \ A ) ) C_ A | 
						
							| 3 | 1 | ackbij1lem11 |  |-  ( ( A e. ( ~P _om i^i Fin ) /\ ( A \ |^| ( _om \ A ) ) C_ A ) -> ( A \ |^| ( _om \ A ) ) e. ( ~P _om i^i Fin ) ) | 
						
							| 4 | 2 3 | mpan2 |  |-  ( A e. ( ~P _om i^i Fin ) -> ( A \ |^| ( _om \ A ) ) e. ( ~P _om i^i Fin ) ) | 
						
							| 5 |  | difss |  |-  ( _om \ A ) C_ _om | 
						
							| 6 |  | omsson |  |-  _om C_ On | 
						
							| 7 | 5 6 | sstri |  |-  ( _om \ A ) C_ On | 
						
							| 8 |  | ominf |  |-  -. _om e. Fin | 
						
							| 9 |  | elinel2 |  |-  ( A e. ( ~P _om i^i Fin ) -> A e. Fin ) | 
						
							| 10 |  | difinf |  |-  ( ( -. _om e. Fin /\ A e. Fin ) -> -. ( _om \ A ) e. Fin ) | 
						
							| 11 | 8 9 10 | sylancr |  |-  ( A e. ( ~P _om i^i Fin ) -> -. ( _om \ A ) e. Fin ) | 
						
							| 12 |  | 0fi |  |-  (/) e. Fin | 
						
							| 13 |  | eleq1 |  |-  ( ( _om \ A ) = (/) -> ( ( _om \ A ) e. Fin <-> (/) e. Fin ) ) | 
						
							| 14 | 12 13 | mpbiri |  |-  ( ( _om \ A ) = (/) -> ( _om \ A ) e. Fin ) | 
						
							| 15 | 14 | necon3bi |  |-  ( -. ( _om \ A ) e. Fin -> ( _om \ A ) =/= (/) ) | 
						
							| 16 | 11 15 | syl |  |-  ( A e. ( ~P _om i^i Fin ) -> ( _om \ A ) =/= (/) ) | 
						
							| 17 |  | onint |  |-  ( ( ( _om \ A ) C_ On /\ ( _om \ A ) =/= (/) ) -> |^| ( _om \ A ) e. ( _om \ A ) ) | 
						
							| 18 | 7 16 17 | sylancr |  |-  ( A e. ( ~P _om i^i Fin ) -> |^| ( _om \ A ) e. ( _om \ A ) ) | 
						
							| 19 | 18 | eldifad |  |-  ( A e. ( ~P _om i^i Fin ) -> |^| ( _om \ A ) e. _om ) | 
						
							| 20 |  | ackbij1lem4 |  |-  ( |^| ( _om \ A ) e. _om -> { |^| ( _om \ A ) } e. ( ~P _om i^i Fin ) ) | 
						
							| 21 | 19 20 | syl |  |-  ( A e. ( ~P _om i^i Fin ) -> { |^| ( _om \ A ) } e. ( ~P _om i^i Fin ) ) | 
						
							| 22 |  | ackbij1lem6 |  |-  ( ( ( A \ |^| ( _om \ A ) ) e. ( ~P _om i^i Fin ) /\ { |^| ( _om \ A ) } e. ( ~P _om i^i Fin ) ) -> ( ( A \ |^| ( _om \ A ) ) u. { |^| ( _om \ A ) } ) e. ( ~P _om i^i Fin ) ) | 
						
							| 23 | 4 21 22 | syl2anc |  |-  ( A e. ( ~P _om i^i Fin ) -> ( ( A \ |^| ( _om \ A ) ) u. { |^| ( _om \ A ) } ) e. ( ~P _om i^i Fin ) ) | 
						
							| 24 | 18 | eldifbd |  |-  ( A e. ( ~P _om i^i Fin ) -> -. |^| ( _om \ A ) e. A ) | 
						
							| 25 |  | disjsn |  |-  ( ( A i^i { |^| ( _om \ A ) } ) = (/) <-> -. |^| ( _om \ A ) e. A ) | 
						
							| 26 | 24 25 | sylibr |  |-  ( A e. ( ~P _om i^i Fin ) -> ( A i^i { |^| ( _om \ A ) } ) = (/) ) | 
						
							| 27 |  | ssdisj |  |-  ( ( ( A \ |^| ( _om \ A ) ) C_ A /\ ( A i^i { |^| ( _om \ A ) } ) = (/) ) -> ( ( A \ |^| ( _om \ A ) ) i^i { |^| ( _om \ A ) } ) = (/) ) | 
						
							| 28 | 2 26 27 | sylancr |  |-  ( A e. ( ~P _om i^i Fin ) -> ( ( A \ |^| ( _om \ A ) ) i^i { |^| ( _om \ A ) } ) = (/) ) | 
						
							| 29 | 1 | ackbij1lem9 |  |-  ( ( ( A \ |^| ( _om \ A ) ) e. ( ~P _om i^i Fin ) /\ { |^| ( _om \ A ) } e. ( ~P _om i^i Fin ) /\ ( ( A \ |^| ( _om \ A ) ) i^i { |^| ( _om \ A ) } ) = (/) ) -> ( F ` ( ( A \ |^| ( _om \ A ) ) u. { |^| ( _om \ A ) } ) ) = ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o ( F ` { |^| ( _om \ A ) } ) ) ) | 
						
							| 30 | 4 21 28 29 | syl3anc |  |-  ( A e. ( ~P _om i^i Fin ) -> ( F ` ( ( A \ |^| ( _om \ A ) ) u. { |^| ( _om \ A ) } ) ) = ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o ( F ` { |^| ( _om \ A ) } ) ) ) | 
						
							| 31 | 1 | ackbij1lem14 |  |-  ( |^| ( _om \ A ) e. _om -> ( F ` { |^| ( _om \ A ) } ) = suc ( F ` |^| ( _om \ A ) ) ) | 
						
							| 32 | 19 31 | syl |  |-  ( A e. ( ~P _om i^i Fin ) -> ( F ` { |^| ( _om \ A ) } ) = suc ( F ` |^| ( _om \ A ) ) ) | 
						
							| 33 | 32 | oveq2d |  |-  ( A e. ( ~P _om i^i Fin ) -> ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o ( F ` { |^| ( _om \ A ) } ) ) = ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o suc ( F ` |^| ( _om \ A ) ) ) ) | 
						
							| 34 | 1 | ackbij1lem10 |  |-  F : ( ~P _om i^i Fin ) --> _om | 
						
							| 35 | 34 | ffvelcdmi |  |-  ( ( A \ |^| ( _om \ A ) ) e. ( ~P _om i^i Fin ) -> ( F ` ( A \ |^| ( _om \ A ) ) ) e. _om ) | 
						
							| 36 | 4 35 | syl |  |-  ( A e. ( ~P _om i^i Fin ) -> ( F ` ( A \ |^| ( _om \ A ) ) ) e. _om ) | 
						
							| 37 |  | ackbij1lem3 |  |-  ( |^| ( _om \ A ) e. _om -> |^| ( _om \ A ) e. ( ~P _om i^i Fin ) ) | 
						
							| 38 | 19 37 | syl |  |-  ( A e. ( ~P _om i^i Fin ) -> |^| ( _om \ A ) e. ( ~P _om i^i Fin ) ) | 
						
							| 39 | 34 | ffvelcdmi |  |-  ( |^| ( _om \ A ) e. ( ~P _om i^i Fin ) -> ( F ` |^| ( _om \ A ) ) e. _om ) | 
						
							| 40 | 38 39 | syl |  |-  ( A e. ( ~P _om i^i Fin ) -> ( F ` |^| ( _om \ A ) ) e. _om ) | 
						
							| 41 |  | nnasuc |  |-  ( ( ( F ` ( A \ |^| ( _om \ A ) ) ) e. _om /\ ( F ` |^| ( _om \ A ) ) e. _om ) -> ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o suc ( F ` |^| ( _om \ A ) ) ) = suc ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o ( F ` |^| ( _om \ A ) ) ) ) | 
						
							| 42 | 36 40 41 | syl2anc |  |-  ( A e. ( ~P _om i^i Fin ) -> ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o suc ( F ` |^| ( _om \ A ) ) ) = suc ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o ( F ` |^| ( _om \ A ) ) ) ) | 
						
							| 43 |  | disjdifr |  |-  ( ( A \ |^| ( _om \ A ) ) i^i |^| ( _om \ A ) ) = (/) | 
						
							| 44 | 43 | a1i |  |-  ( A e. ( ~P _om i^i Fin ) -> ( ( A \ |^| ( _om \ A ) ) i^i |^| ( _om \ A ) ) = (/) ) | 
						
							| 45 | 1 | ackbij1lem9 |  |-  ( ( ( A \ |^| ( _om \ A ) ) e. ( ~P _om i^i Fin ) /\ |^| ( _om \ A ) e. ( ~P _om i^i Fin ) /\ ( ( A \ |^| ( _om \ A ) ) i^i |^| ( _om \ A ) ) = (/) ) -> ( F ` ( ( A \ |^| ( _om \ A ) ) u. |^| ( _om \ A ) ) ) = ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o ( F ` |^| ( _om \ A ) ) ) ) | 
						
							| 46 | 4 38 44 45 | syl3anc |  |-  ( A e. ( ~P _om i^i Fin ) -> ( F ` ( ( A \ |^| ( _om \ A ) ) u. |^| ( _om \ A ) ) ) = ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o ( F ` |^| ( _om \ A ) ) ) ) | 
						
							| 47 |  | uncom |  |-  ( ( A \ |^| ( _om \ A ) ) u. |^| ( _om \ A ) ) = ( |^| ( _om \ A ) u. ( A \ |^| ( _om \ A ) ) ) | 
						
							| 48 |  | onnmin |  |-  ( ( ( _om \ A ) C_ On /\ a e. ( _om \ A ) ) -> -. a e. |^| ( _om \ A ) ) | 
						
							| 49 | 7 48 | mpan |  |-  ( a e. ( _om \ A ) -> -. a e. |^| ( _om \ A ) ) | 
						
							| 50 | 49 | con2i |  |-  ( a e. |^| ( _om \ A ) -> -. a e. ( _om \ A ) ) | 
						
							| 51 | 50 | adantl |  |-  ( ( A e. ( ~P _om i^i Fin ) /\ a e. |^| ( _om \ A ) ) -> -. a e. ( _om \ A ) ) | 
						
							| 52 |  | ordom |  |-  Ord _om | 
						
							| 53 |  | ordelss |  |-  ( ( Ord _om /\ |^| ( _om \ A ) e. _om ) -> |^| ( _om \ A ) C_ _om ) | 
						
							| 54 | 52 19 53 | sylancr |  |-  ( A e. ( ~P _om i^i Fin ) -> |^| ( _om \ A ) C_ _om ) | 
						
							| 55 | 54 | sselda |  |-  ( ( A e. ( ~P _om i^i Fin ) /\ a e. |^| ( _om \ A ) ) -> a e. _om ) | 
						
							| 56 |  | eldif |  |-  ( a e. ( _om \ A ) <-> ( a e. _om /\ -. a e. A ) ) | 
						
							| 57 | 56 | simplbi2 |  |-  ( a e. _om -> ( -. a e. A -> a e. ( _om \ A ) ) ) | 
						
							| 58 | 57 | orrd |  |-  ( a e. _om -> ( a e. A \/ a e. ( _om \ A ) ) ) | 
						
							| 59 | 58 | orcomd |  |-  ( a e. _om -> ( a e. ( _om \ A ) \/ a e. A ) ) | 
						
							| 60 | 55 59 | syl |  |-  ( ( A e. ( ~P _om i^i Fin ) /\ a e. |^| ( _om \ A ) ) -> ( a e. ( _om \ A ) \/ a e. A ) ) | 
						
							| 61 |  | orel1 |  |-  ( -. a e. ( _om \ A ) -> ( ( a e. ( _om \ A ) \/ a e. A ) -> a e. A ) ) | 
						
							| 62 | 51 60 61 | sylc |  |-  ( ( A e. ( ~P _om i^i Fin ) /\ a e. |^| ( _om \ A ) ) -> a e. A ) | 
						
							| 63 | 62 | ex |  |-  ( A e. ( ~P _om i^i Fin ) -> ( a e. |^| ( _om \ A ) -> a e. A ) ) | 
						
							| 64 | 63 | ssrdv |  |-  ( A e. ( ~P _om i^i Fin ) -> |^| ( _om \ A ) C_ A ) | 
						
							| 65 |  | undif |  |-  ( |^| ( _om \ A ) C_ A <-> ( |^| ( _om \ A ) u. ( A \ |^| ( _om \ A ) ) ) = A ) | 
						
							| 66 | 64 65 | sylib |  |-  ( A e. ( ~P _om i^i Fin ) -> ( |^| ( _om \ A ) u. ( A \ |^| ( _om \ A ) ) ) = A ) | 
						
							| 67 | 47 66 | eqtrid |  |-  ( A e. ( ~P _om i^i Fin ) -> ( ( A \ |^| ( _om \ A ) ) u. |^| ( _om \ A ) ) = A ) | 
						
							| 68 | 67 | fveq2d |  |-  ( A e. ( ~P _om i^i Fin ) -> ( F ` ( ( A \ |^| ( _om \ A ) ) u. |^| ( _om \ A ) ) ) = ( F ` A ) ) | 
						
							| 69 | 46 68 | eqtr3d |  |-  ( A e. ( ~P _om i^i Fin ) -> ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o ( F ` |^| ( _om \ A ) ) ) = ( F ` A ) ) | 
						
							| 70 |  | suceq |  |-  ( ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o ( F ` |^| ( _om \ A ) ) ) = ( F ` A ) -> suc ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o ( F ` |^| ( _om \ A ) ) ) = suc ( F ` A ) ) | 
						
							| 71 | 69 70 | syl |  |-  ( A e. ( ~P _om i^i Fin ) -> suc ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o ( F ` |^| ( _om \ A ) ) ) = suc ( F ` A ) ) | 
						
							| 72 | 42 71 | eqtrd |  |-  ( A e. ( ~P _om i^i Fin ) -> ( ( F ` ( A \ |^| ( _om \ A ) ) ) +o suc ( F ` |^| ( _om \ A ) ) ) = suc ( F ` A ) ) | 
						
							| 73 | 30 33 72 | 3eqtrd |  |-  ( A e. ( ~P _om i^i Fin ) -> ( F ` ( ( A \ |^| ( _om \ A ) ) u. { |^| ( _om \ A ) } ) ) = suc ( F ` A ) ) | 
						
							| 74 |  | fveqeq2 |  |-  ( b = ( ( A \ |^| ( _om \ A ) ) u. { |^| ( _om \ A ) } ) -> ( ( F ` b ) = suc ( F ` A ) <-> ( F ` ( ( A \ |^| ( _om \ A ) ) u. { |^| ( _om \ A ) } ) ) = suc ( F ` A ) ) ) | 
						
							| 75 | 74 | rspcev |  |-  ( ( ( ( A \ |^| ( _om \ A ) ) u. { |^| ( _om \ A ) } ) e. ( ~P _om i^i Fin ) /\ ( F ` ( ( A \ |^| ( _om \ A ) ) u. { |^| ( _om \ A ) } ) ) = suc ( F ` A ) ) -> E. b e. ( ~P _om i^i Fin ) ( F ` b ) = suc ( F ` A ) ) | 
						
							| 76 | 23 73 75 | syl2anc |  |-  ( A e. ( ~P _om i^i Fin ) -> E. b e. ( ~P _om i^i Fin ) ( F ` b ) = suc ( F ` A ) ) |