| 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 | 1 | ackbij1lem8 |  |-  ( A e. _om -> ( F ` { A } ) = ( card ` ~P A ) ) | 
						
							| 3 |  | pweq |  |-  ( a = (/) -> ~P a = ~P (/) ) | 
						
							| 4 | 3 | fveq2d |  |-  ( a = (/) -> ( card ` ~P a ) = ( card ` ~P (/) ) ) | 
						
							| 5 |  | fveq2 |  |-  ( a = (/) -> ( F ` a ) = ( F ` (/) ) ) | 
						
							| 6 |  | suceq |  |-  ( ( F ` a ) = ( F ` (/) ) -> suc ( F ` a ) = suc ( F ` (/) ) ) | 
						
							| 7 | 5 6 | syl |  |-  ( a = (/) -> suc ( F ` a ) = suc ( F ` (/) ) ) | 
						
							| 8 | 4 7 | eqeq12d |  |-  ( a = (/) -> ( ( card ` ~P a ) = suc ( F ` a ) <-> ( card ` ~P (/) ) = suc ( F ` (/) ) ) ) | 
						
							| 9 |  | pweq |  |-  ( a = b -> ~P a = ~P b ) | 
						
							| 10 | 9 | fveq2d |  |-  ( a = b -> ( card ` ~P a ) = ( card ` ~P b ) ) | 
						
							| 11 |  | fveq2 |  |-  ( a = b -> ( F ` a ) = ( F ` b ) ) | 
						
							| 12 |  | suceq |  |-  ( ( F ` a ) = ( F ` b ) -> suc ( F ` a ) = suc ( F ` b ) ) | 
						
							| 13 | 11 12 | syl |  |-  ( a = b -> suc ( F ` a ) = suc ( F ` b ) ) | 
						
							| 14 | 10 13 | eqeq12d |  |-  ( a = b -> ( ( card ` ~P a ) = suc ( F ` a ) <-> ( card ` ~P b ) = suc ( F ` b ) ) ) | 
						
							| 15 |  | pweq |  |-  ( a = suc b -> ~P a = ~P suc b ) | 
						
							| 16 | 15 | fveq2d |  |-  ( a = suc b -> ( card ` ~P a ) = ( card ` ~P suc b ) ) | 
						
							| 17 |  | fveq2 |  |-  ( a = suc b -> ( F ` a ) = ( F ` suc b ) ) | 
						
							| 18 |  | suceq |  |-  ( ( F ` a ) = ( F ` suc b ) -> suc ( F ` a ) = suc ( F ` suc b ) ) | 
						
							| 19 | 17 18 | syl |  |-  ( a = suc b -> suc ( F ` a ) = suc ( F ` suc b ) ) | 
						
							| 20 | 16 19 | eqeq12d |  |-  ( a = suc b -> ( ( card ` ~P a ) = suc ( F ` a ) <-> ( card ` ~P suc b ) = suc ( F ` suc b ) ) ) | 
						
							| 21 |  | pweq |  |-  ( a = A -> ~P a = ~P A ) | 
						
							| 22 | 21 | fveq2d |  |-  ( a = A -> ( card ` ~P a ) = ( card ` ~P A ) ) | 
						
							| 23 |  | fveq2 |  |-  ( a = A -> ( F ` a ) = ( F ` A ) ) | 
						
							| 24 |  | suceq |  |-  ( ( F ` a ) = ( F ` A ) -> suc ( F ` a ) = suc ( F ` A ) ) | 
						
							| 25 | 23 24 | syl |  |-  ( a = A -> suc ( F ` a ) = suc ( F ` A ) ) | 
						
							| 26 | 22 25 | eqeq12d |  |-  ( a = A -> ( ( card ` ~P a ) = suc ( F ` a ) <-> ( card ` ~P A ) = suc ( F ` A ) ) ) | 
						
							| 27 |  | df-1o |  |-  1o = suc (/) | 
						
							| 28 |  | pw0 |  |-  ~P (/) = { (/) } | 
						
							| 29 | 28 | fveq2i |  |-  ( card ` ~P (/) ) = ( card ` { (/) } ) | 
						
							| 30 |  | 0ex |  |-  (/) e. _V | 
						
							| 31 |  | cardsn |  |-  ( (/) e. _V -> ( card ` { (/) } ) = 1o ) | 
						
							| 32 | 30 31 | ax-mp |  |-  ( card ` { (/) } ) = 1o | 
						
							| 33 | 29 32 | eqtri |  |-  ( card ` ~P (/) ) = 1o | 
						
							| 34 | 1 | ackbij1lem13 |  |-  ( F ` (/) ) = (/) | 
						
							| 35 |  | suceq |  |-  ( ( F ` (/) ) = (/) -> suc ( F ` (/) ) = suc (/) ) | 
						
							| 36 | 34 35 | ax-mp |  |-  suc ( F ` (/) ) = suc (/) | 
						
							| 37 | 27 33 36 | 3eqtr4i |  |-  ( card ` ~P (/) ) = suc ( F ` (/) ) | 
						
							| 38 |  | oveq2 |  |-  ( ( card ` ~P b ) = suc ( F ` b ) -> ( ( card ` ~P b ) +o ( card ` ~P b ) ) = ( ( card ` ~P b ) +o suc ( F ` b ) ) ) | 
						
							| 39 | 38 | adantl |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> ( ( card ` ~P b ) +o ( card ` ~P b ) ) = ( ( card ` ~P b ) +o suc ( F ` b ) ) ) | 
						
							| 40 |  | ackbij1lem5 |  |-  ( b e. _om -> ( card ` ~P suc b ) = ( ( card ` ~P b ) +o ( card ` ~P b ) ) ) | 
						
							| 41 | 40 | adantr |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> ( card ` ~P suc b ) = ( ( card ` ~P b ) +o ( card ` ~P b ) ) ) | 
						
							| 42 |  | df-suc |  |-  suc b = ( b u. { b } ) | 
						
							| 43 | 42 | equncomi |  |-  suc b = ( { b } u. b ) | 
						
							| 44 | 43 | fveq2i |  |-  ( F ` suc b ) = ( F ` ( { b } u. b ) ) | 
						
							| 45 |  | ackbij1lem4 |  |-  ( b e. _om -> { b } e. ( ~P _om i^i Fin ) ) | 
						
							| 46 | 45 | adantr |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> { b } e. ( ~P _om i^i Fin ) ) | 
						
							| 47 |  | ackbij1lem3 |  |-  ( b e. _om -> b e. ( ~P _om i^i Fin ) ) | 
						
							| 48 | 47 | adantr |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> b e. ( ~P _om i^i Fin ) ) | 
						
							| 49 |  | incom |  |-  ( { b } i^i b ) = ( b i^i { b } ) | 
						
							| 50 |  | nnord |  |-  ( b e. _om -> Ord b ) | 
						
							| 51 |  | orddisj |  |-  ( Ord b -> ( b i^i { b } ) = (/) ) | 
						
							| 52 | 50 51 | syl |  |-  ( b e. _om -> ( b i^i { b } ) = (/) ) | 
						
							| 53 | 49 52 | eqtrid |  |-  ( b e. _om -> ( { b } i^i b ) = (/) ) | 
						
							| 54 | 53 | adantr |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> ( { b } i^i b ) = (/) ) | 
						
							| 55 | 1 | ackbij1lem9 |  |-  ( ( { b } e. ( ~P _om i^i Fin ) /\ b e. ( ~P _om i^i Fin ) /\ ( { b } i^i b ) = (/) ) -> ( F ` ( { b } u. b ) ) = ( ( F ` { b } ) +o ( F ` b ) ) ) | 
						
							| 56 | 46 48 54 55 | syl3anc |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> ( F ` ( { b } u. b ) ) = ( ( F ` { b } ) +o ( F ` b ) ) ) | 
						
							| 57 | 1 | ackbij1lem8 |  |-  ( b e. _om -> ( F ` { b } ) = ( card ` ~P b ) ) | 
						
							| 58 | 57 | adantr |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> ( F ` { b } ) = ( card ` ~P b ) ) | 
						
							| 59 | 58 | oveq1d |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> ( ( F ` { b } ) +o ( F ` b ) ) = ( ( card ` ~P b ) +o ( F ` b ) ) ) | 
						
							| 60 | 56 59 | eqtrd |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> ( F ` ( { b } u. b ) ) = ( ( card ` ~P b ) +o ( F ` b ) ) ) | 
						
							| 61 | 44 60 | eqtrid |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> ( F ` suc b ) = ( ( card ` ~P b ) +o ( F ` b ) ) ) | 
						
							| 62 |  | suceq |  |-  ( ( F ` suc b ) = ( ( card ` ~P b ) +o ( F ` b ) ) -> suc ( F ` suc b ) = suc ( ( card ` ~P b ) +o ( F ` b ) ) ) | 
						
							| 63 | 61 62 | syl |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> suc ( F ` suc b ) = suc ( ( card ` ~P b ) +o ( F ` b ) ) ) | 
						
							| 64 |  | nnfi |  |-  ( b e. _om -> b e. Fin ) | 
						
							| 65 |  | pwfi |  |-  ( b e. Fin <-> ~P b e. Fin ) | 
						
							| 66 | 64 65 | sylib |  |-  ( b e. _om -> ~P b e. Fin ) | 
						
							| 67 | 66 | adantr |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> ~P b e. Fin ) | 
						
							| 68 |  | ficardom |  |-  ( ~P b e. Fin -> ( card ` ~P b ) e. _om ) | 
						
							| 69 | 67 68 | syl |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> ( card ` ~P b ) e. _om ) | 
						
							| 70 | 1 | ackbij1lem10 |  |-  F : ( ~P _om i^i Fin ) --> _om | 
						
							| 71 | 70 | ffvelcdmi |  |-  ( b e. ( ~P _om i^i Fin ) -> ( F ` b ) e. _om ) | 
						
							| 72 | 48 71 | syl |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> ( F ` b ) e. _om ) | 
						
							| 73 |  | nnasuc |  |-  ( ( ( card ` ~P b ) e. _om /\ ( F ` b ) e. _om ) -> ( ( card ` ~P b ) +o suc ( F ` b ) ) = suc ( ( card ` ~P b ) +o ( F ` b ) ) ) | 
						
							| 74 | 69 72 73 | syl2anc |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> ( ( card ` ~P b ) +o suc ( F ` b ) ) = suc ( ( card ` ~P b ) +o ( F ` b ) ) ) | 
						
							| 75 | 63 74 | eqtr4d |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> suc ( F ` suc b ) = ( ( card ` ~P b ) +o suc ( F ` b ) ) ) | 
						
							| 76 | 39 41 75 | 3eqtr4d |  |-  ( ( b e. _om /\ ( card ` ~P b ) = suc ( F ` b ) ) -> ( card ` ~P suc b ) = suc ( F ` suc b ) ) | 
						
							| 77 | 76 | ex |  |-  ( b e. _om -> ( ( card ` ~P b ) = suc ( F ` b ) -> ( card ` ~P suc b ) = suc ( F ` suc b ) ) ) | 
						
							| 78 | 8 14 20 26 37 77 | finds |  |-  ( A e. _om -> ( card ` ~P A ) = suc ( F ` A ) ) | 
						
							| 79 | 2 78 | eqtrd |  |-  ( A e. _om -> ( F ` { A } ) = suc ( F ` A ) ) |