| Step | Hyp | Ref | Expression | 
						
							| 1 |  | naddcnff |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> ( oF +o |` ( S X. S ) ) : ( S X. S ) --> S ) | 
						
							| 2 |  | simpr |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ f e. S ) -> f e. S ) | 
						
							| 3 |  | peano1 |  |-  (/) e. _om | 
						
							| 4 |  | fconst6g |  |-  ( (/) e. _om -> ( X X. { (/) } ) : X --> _om ) | 
						
							| 5 | 3 4 | mp1i |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> ( X X. { (/) } ) : X --> _om ) | 
						
							| 6 |  | simpl |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> X e. On ) | 
						
							| 7 | 3 | a1i |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> (/) e. _om ) | 
						
							| 8 | 6 7 | fczfsuppd |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> ( X X. { (/) } ) finSupp (/) ) | 
						
							| 9 |  | simpr |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> S = dom ( _om CNF X ) ) | 
						
							| 10 | 9 | eleq2d |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> ( ( X X. { (/) } ) e. S <-> ( X X. { (/) } ) e. dom ( _om CNF X ) ) ) | 
						
							| 11 |  | eqid |  |-  dom ( _om CNF X ) = dom ( _om CNF X ) | 
						
							| 12 |  | omelon |  |-  _om e. On | 
						
							| 13 | 12 | a1i |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> _om e. On ) | 
						
							| 14 | 11 13 6 | cantnfs |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> ( ( X X. { (/) } ) e. dom ( _om CNF X ) <-> ( ( X X. { (/) } ) : X --> _om /\ ( X X. { (/) } ) finSupp (/) ) ) ) | 
						
							| 15 | 10 14 | bitrd |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> ( ( X X. { (/) } ) e. S <-> ( ( X X. { (/) } ) : X --> _om /\ ( X X. { (/) } ) finSupp (/) ) ) ) | 
						
							| 16 | 5 8 15 | mpbir2and |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> ( X X. { (/) } ) e. S ) | 
						
							| 17 | 16 | adantr |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ f e. S ) -> ( X X. { (/) } ) e. S ) | 
						
							| 18 |  | simpl |  |-  ( ( f e. S /\ ( X X. { (/) } ) e. S ) -> f e. S ) | 
						
							| 19 | 18 | adantl |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) -> f e. S ) | 
						
							| 20 |  | simpr |  |-  ( ( f e. S /\ ( X X. { (/) } ) e. S ) -> ( X X. { (/) } ) e. S ) | 
						
							| 21 | 20 | adantl |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) -> ( X X. { (/) } ) e. S ) | 
						
							| 22 | 19 21 | ovresd |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) -> ( f ( oF +o |` ( S X. S ) ) ( X X. { (/) } ) ) = ( f oF +o ( X X. { (/) } ) ) ) | 
						
							| 23 | 9 | eleq2d |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> ( f e. S <-> f e. dom ( _om CNF X ) ) ) | 
						
							| 24 | 11 13 6 | cantnfs |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> ( f e. dom ( _om CNF X ) <-> ( f : X --> _om /\ f finSupp (/) ) ) ) | 
						
							| 25 | 23 24 | bitrd |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> ( f e. S <-> ( f : X --> _om /\ f finSupp (/) ) ) ) | 
						
							| 26 | 25 | biimpd |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> ( f e. S -> ( f : X --> _om /\ f finSupp (/) ) ) ) | 
						
							| 27 |  | simpl |  |-  ( ( f : X --> _om /\ f finSupp (/) ) -> f : X --> _om ) | 
						
							| 28 | 18 26 27 | syl56 |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> ( ( f e. S /\ ( X X. { (/) } ) e. S ) -> f : X --> _om ) ) | 
						
							| 29 | 28 | imp |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) -> f : X --> _om ) | 
						
							| 30 | 29 | ffnd |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) -> f Fn X ) | 
						
							| 31 |  | fnconstg |  |-  ( (/) e. _om -> ( X X. { (/) } ) Fn X ) | 
						
							| 32 | 3 31 | mp1i |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) -> ( X X. { (/) } ) Fn X ) | 
						
							| 33 | 6 | adantr |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) -> X e. On ) | 
						
							| 34 |  | inidm |  |-  ( X i^i X ) = X | 
						
							| 35 | 30 32 33 33 34 | offn |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) -> ( f oF +o ( X X. { (/) } ) ) Fn X ) | 
						
							| 36 | 30 | adantr |  |-  ( ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) /\ x e. X ) -> f Fn X ) | 
						
							| 37 | 3 31 | mp1i |  |-  ( ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) /\ x e. X ) -> ( X X. { (/) } ) Fn X ) | 
						
							| 38 |  | simplll |  |-  ( ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) /\ x e. X ) -> X e. On ) | 
						
							| 39 |  | simpr |  |-  ( ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) /\ x e. X ) -> x e. X ) | 
						
							| 40 |  | fnfvof |  |-  ( ( ( f Fn X /\ ( X X. { (/) } ) Fn X ) /\ ( X e. On /\ x e. X ) ) -> ( ( f oF +o ( X X. { (/) } ) ) ` x ) = ( ( f ` x ) +o ( ( X X. { (/) } ) ` x ) ) ) | 
						
							| 41 | 36 37 38 39 40 | syl22anc |  |-  ( ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) /\ x e. X ) -> ( ( f oF +o ( X X. { (/) } ) ) ` x ) = ( ( f ` x ) +o ( ( X X. { (/) } ) ` x ) ) ) | 
						
							| 42 | 3 | a1i |  |-  ( ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) /\ x e. X ) -> (/) e. _om ) | 
						
							| 43 |  | fvconst2g |  |-  ( ( (/) e. _om /\ x e. X ) -> ( ( X X. { (/) } ) ` x ) = (/) ) | 
						
							| 44 | 42 39 43 | syl2anc |  |-  ( ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) /\ x e. X ) -> ( ( X X. { (/) } ) ` x ) = (/) ) | 
						
							| 45 | 44 | oveq2d |  |-  ( ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) /\ x e. X ) -> ( ( f ` x ) +o ( ( X X. { (/) } ) ` x ) ) = ( ( f ` x ) +o (/) ) ) | 
						
							| 46 | 29 | ffvelcdmda |  |-  ( ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) /\ x e. X ) -> ( f ` x ) e. _om ) | 
						
							| 47 |  | nnon |  |-  ( ( f ` x ) e. _om -> ( f ` x ) e. On ) | 
						
							| 48 |  | oa0 |  |-  ( ( f ` x ) e. On -> ( ( f ` x ) +o (/) ) = ( f ` x ) ) | 
						
							| 49 | 46 47 48 | 3syl |  |-  ( ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) /\ x e. X ) -> ( ( f ` x ) +o (/) ) = ( f ` x ) ) | 
						
							| 50 | 41 45 49 | 3eqtrd |  |-  ( ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) /\ x e. X ) -> ( ( f oF +o ( X X. { (/) } ) ) ` x ) = ( f ` x ) ) | 
						
							| 51 | 35 30 50 | eqfnfvd |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) -> ( f oF +o ( X X. { (/) } ) ) = f ) | 
						
							| 52 | 22 51 | eqtr2d |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ ( f e. S /\ ( X X. { (/) } ) e. S ) ) -> f = ( f ( oF +o |` ( S X. S ) ) ( X X. { (/) } ) ) ) | 
						
							| 53 | 52 | expr |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ f e. S ) -> ( ( X X. { (/) } ) e. S -> f = ( f ( oF +o |` ( S X. S ) ) ( X X. { (/) } ) ) ) ) | 
						
							| 54 | 17 53 | jcai |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ f e. S ) -> ( ( X X. { (/) } ) e. S /\ f = ( f ( oF +o |` ( S X. S ) ) ( X X. { (/) } ) ) ) ) | 
						
							| 55 |  | oveq2 |  |-  ( z = ( X X. { (/) } ) -> ( f ( oF +o |` ( S X. S ) ) z ) = ( f ( oF +o |` ( S X. S ) ) ( X X. { (/) } ) ) ) | 
						
							| 56 | 55 | rspceeqv |  |-  ( ( ( X X. { (/) } ) e. S /\ f = ( f ( oF +o |` ( S X. S ) ) ( X X. { (/) } ) ) ) -> E. z e. S f = ( f ( oF +o |` ( S X. S ) ) z ) ) | 
						
							| 57 | 54 56 | syl |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ f e. S ) -> E. z e. S f = ( f ( oF +o |` ( S X. S ) ) z ) ) | 
						
							| 58 |  | oveq1 |  |-  ( g = f -> ( g ( oF +o |` ( S X. S ) ) z ) = ( f ( oF +o |` ( S X. S ) ) z ) ) | 
						
							| 59 | 58 | eqeq2d |  |-  ( g = f -> ( f = ( g ( oF +o |` ( S X. S ) ) z ) <-> f = ( f ( oF +o |` ( S X. S ) ) z ) ) ) | 
						
							| 60 | 59 | rexbidv |  |-  ( g = f -> ( E. z e. S f = ( g ( oF +o |` ( S X. S ) ) z ) <-> E. z e. S f = ( f ( oF +o |` ( S X. S ) ) z ) ) ) | 
						
							| 61 | 60 | rspcev |  |-  ( ( f e. S /\ E. z e. S f = ( f ( oF +o |` ( S X. S ) ) z ) ) -> E. g e. S E. z e. S f = ( g ( oF +o |` ( S X. S ) ) z ) ) | 
						
							| 62 | 2 57 61 | syl2anc |  |-  ( ( ( X e. On /\ S = dom ( _om CNF X ) ) /\ f e. S ) -> E. g e. S E. z e. S f = ( g ( oF +o |` ( S X. S ) ) z ) ) | 
						
							| 63 | 62 | ralrimiva |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> A. f e. S E. g e. S E. z e. S f = ( g ( oF +o |` ( S X. S ) ) z ) ) | 
						
							| 64 |  | foov |  |-  ( ( oF +o |` ( S X. S ) ) : ( S X. S ) -onto-> S <-> ( ( oF +o |` ( S X. S ) ) : ( S X. S ) --> S /\ A. f e. S E. g e. S E. z e. S f = ( g ( oF +o |` ( S X. S ) ) z ) ) ) | 
						
							| 65 | 1 63 64 | sylanbrc |  |-  ( ( X e. On /\ S = dom ( _om CNF X ) ) -> ( oF +o |` ( S X. S ) ) : ( S X. S ) -onto-> S ) |