| Step | Hyp | Ref | Expression | 
						
							| 1 |  | df-ttrcl |  |-  t++ R = { <. x , y >. | E. n e. ( _om \ 1o ) E. f ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) } | 
						
							| 2 | 1 | rneqi |  |-  ran t++ R = ran { <. x , y >. | E. n e. ( _om \ 1o ) E. f ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) } | 
						
							| 3 |  | rnopab |  |-  ran { <. x , y >. | E. n e. ( _om \ 1o ) E. f ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) } = { y | E. x E. n e. ( _om \ 1o ) E. f ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) } | 
						
							| 4 | 2 3 | eqtri |  |-  ran t++ R = { y | E. x E. n e. ( _om \ 1o ) E. f ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) } | 
						
							| 5 |  | fveq2 |  |-  ( a = U. n -> ( f ` a ) = ( f ` U. n ) ) | 
						
							| 6 |  | suceq |  |-  ( a = U. n -> suc a = suc U. n ) | 
						
							| 7 | 6 | fveq2d |  |-  ( a = U. n -> ( f ` suc a ) = ( f ` suc U. n ) ) | 
						
							| 8 | 5 7 | breq12d |  |-  ( a = U. n -> ( ( f ` a ) R ( f ` suc a ) <-> ( f ` U. n ) R ( f ` suc U. n ) ) ) | 
						
							| 9 |  | simpr3 |  |-  ( ( n e. ( _om \ 1o ) /\ ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) ) -> A. a e. n ( f ` a ) R ( f ` suc a ) ) | 
						
							| 10 |  | df-1o |  |-  1o = suc (/) | 
						
							| 11 | 10 | difeq2i |  |-  ( _om \ 1o ) = ( _om \ suc (/) ) | 
						
							| 12 | 11 | eleq2i |  |-  ( n e. ( _om \ 1o ) <-> n e. ( _om \ suc (/) ) ) | 
						
							| 13 |  | peano1 |  |-  (/) e. _om | 
						
							| 14 |  | eldifsucnn |  |-  ( (/) e. _om -> ( n e. ( _om \ suc (/) ) <-> E. x e. ( _om \ (/) ) n = suc x ) ) | 
						
							| 15 | 13 14 | ax-mp |  |-  ( n e. ( _om \ suc (/) ) <-> E. x e. ( _om \ (/) ) n = suc x ) | 
						
							| 16 |  | dif0 |  |-  ( _om \ (/) ) = _om | 
						
							| 17 | 16 | rexeqi |  |-  ( E. x e. ( _om \ (/) ) n = suc x <-> E. x e. _om n = suc x ) | 
						
							| 18 | 12 15 17 | 3bitri |  |-  ( n e. ( _om \ 1o ) <-> E. x e. _om n = suc x ) | 
						
							| 19 |  | nnord |  |-  ( x e. _om -> Ord x ) | 
						
							| 20 |  | ordunisuc |  |-  ( Ord x -> U. suc x = x ) | 
						
							| 21 | 19 20 | syl |  |-  ( x e. _om -> U. suc x = x ) | 
						
							| 22 |  | vex |  |-  x e. _V | 
						
							| 23 | 22 | sucid |  |-  x e. suc x | 
						
							| 24 | 21 23 | eqeltrdi |  |-  ( x e. _om -> U. suc x e. suc x ) | 
						
							| 25 |  | unieq |  |-  ( n = suc x -> U. n = U. suc x ) | 
						
							| 26 |  | id |  |-  ( n = suc x -> n = suc x ) | 
						
							| 27 | 25 26 | eleq12d |  |-  ( n = suc x -> ( U. n e. n <-> U. suc x e. suc x ) ) | 
						
							| 28 | 24 27 | syl5ibrcom |  |-  ( x e. _om -> ( n = suc x -> U. n e. n ) ) | 
						
							| 29 | 28 | rexlimiv |  |-  ( E. x e. _om n = suc x -> U. n e. n ) | 
						
							| 30 | 18 29 | sylbi |  |-  ( n e. ( _om \ 1o ) -> U. n e. n ) | 
						
							| 31 | 30 | adantr |  |-  ( ( n e. ( _om \ 1o ) /\ ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) ) -> U. n e. n ) | 
						
							| 32 | 8 9 31 | rspcdva |  |-  ( ( n e. ( _om \ 1o ) /\ ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) ) -> ( f ` U. n ) R ( f ` suc U. n ) ) | 
						
							| 33 |  | suceq |  |-  ( U. suc x = x -> suc U. suc x = suc x ) | 
						
							| 34 | 21 33 | syl |  |-  ( x e. _om -> suc U. suc x = suc x ) | 
						
							| 35 |  | suceq |  |-  ( U. n = U. suc x -> suc U. n = suc U. suc x ) | 
						
							| 36 | 25 35 | syl |  |-  ( n = suc x -> suc U. n = suc U. suc x ) | 
						
							| 37 | 36 26 | eqeq12d |  |-  ( n = suc x -> ( suc U. n = n <-> suc U. suc x = suc x ) ) | 
						
							| 38 | 34 37 | syl5ibrcom |  |-  ( x e. _om -> ( n = suc x -> suc U. n = n ) ) | 
						
							| 39 | 38 | rexlimiv |  |-  ( E. x e. _om n = suc x -> suc U. n = n ) | 
						
							| 40 | 18 39 | sylbi |  |-  ( n e. ( _om \ 1o ) -> suc U. n = n ) | 
						
							| 41 | 40 | fveq2d |  |-  ( n e. ( _om \ 1o ) -> ( f ` suc U. n ) = ( f ` n ) ) | 
						
							| 42 | 41 | adantr |  |-  ( ( n e. ( _om \ 1o ) /\ ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) ) -> ( f ` suc U. n ) = ( f ` n ) ) | 
						
							| 43 |  | simpr2r |  |-  ( ( n e. ( _om \ 1o ) /\ ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) ) -> ( f ` n ) = y ) | 
						
							| 44 | 42 43 | eqtrd |  |-  ( ( n e. ( _om \ 1o ) /\ ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) ) -> ( f ` suc U. n ) = y ) | 
						
							| 45 | 32 44 | breqtrd |  |-  ( ( n e. ( _om \ 1o ) /\ ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) ) -> ( f ` U. n ) R y ) | 
						
							| 46 |  | fvex |  |-  ( f ` U. n ) e. _V | 
						
							| 47 |  | vex |  |-  y e. _V | 
						
							| 48 | 46 47 | brelrn |  |-  ( ( f ` U. n ) R y -> y e. ran R ) | 
						
							| 49 | 45 48 | syl |  |-  ( ( n e. ( _om \ 1o ) /\ ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) ) -> y e. ran R ) | 
						
							| 50 | 49 | ex |  |-  ( n e. ( _om \ 1o ) -> ( ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) -> y e. ran R ) ) | 
						
							| 51 | 50 | exlimdv |  |-  ( n e. ( _om \ 1o ) -> ( E. f ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) -> y e. ran R ) ) | 
						
							| 52 | 51 | rexlimiv |  |-  ( E. n e. ( _om \ 1o ) E. f ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) -> y e. ran R ) | 
						
							| 53 | 52 | exlimiv |  |-  ( E. x E. n e. ( _om \ 1o ) E. f ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) -> y e. ran R ) | 
						
							| 54 | 53 | abssi |  |-  { y | E. x E. n e. ( _om \ 1o ) E. f ( f Fn suc n /\ ( ( f ` (/) ) = x /\ ( f ` n ) = y ) /\ A. a e. n ( f ` a ) R ( f ` suc a ) ) } C_ ran R | 
						
							| 55 | 4 54 | eqsstri |  |-  ran t++ R C_ ran R | 
						
							| 56 |  | rnresv |  |-  ran ( R |` _V ) = ran R | 
						
							| 57 |  | relres |  |-  Rel ( R |` _V ) | 
						
							| 58 |  | ssttrcl |  |-  ( Rel ( R |` _V ) -> ( R |` _V ) C_ t++ ( R |` _V ) ) | 
						
							| 59 | 57 58 | ax-mp |  |-  ( R |` _V ) C_ t++ ( R |` _V ) | 
						
							| 60 |  | ttrclresv |  |-  t++ ( R |` _V ) = t++ R | 
						
							| 61 | 59 60 | sseqtri |  |-  ( R |` _V ) C_ t++ R | 
						
							| 62 | 61 | rnssi |  |-  ran ( R |` _V ) C_ ran t++ R | 
						
							| 63 | 56 62 | eqsstrri |  |-  ran R C_ ran t++ R | 
						
							| 64 | 55 63 | eqssi |  |-  ran t++ R = ran R |