Metamath Proof Explorer


Theorem bnj544

Description: Technical lemma for bnj852 . This lemma may no longer be used or have become an indirect lemma of the theorem in question (i.e. a lemma of a lemma... of the theorem). (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

Ref Expression
Hypotheses bnj544.1
|- ( ph' <-> ( f ` (/) ) = _pred ( x , A , R ) )
bnj544.2
|- ( ps' <-> A. i e. _om ( suc i e. m -> ( f ` suc i ) = U_ y e. ( f ` i ) _pred ( y , A , R ) ) )
bnj544.3
|- D = ( _om \ { (/) } )
bnj544.4
|- G = ( f u. { <. m , U_ y e. ( f ` p ) _pred ( y , A , R ) >. } )
bnj544.5
|- ( ta <-> ( f Fn m /\ ph' /\ ps' ) )
bnj544.6
|- ( si <-> ( m e. D /\ n = suc m /\ p e. m ) )
Assertion bnj544
|- ( ( R _FrSe A /\ ta /\ si ) -> G Fn n )

Proof

Step Hyp Ref Expression
1 bnj544.1
 |-  ( ph' <-> ( f ` (/) ) = _pred ( x , A , R ) )
2 bnj544.2
 |-  ( ps' <-> A. i e. _om ( suc i e. m -> ( f ` suc i ) = U_ y e. ( f ` i ) _pred ( y , A , R ) ) )
3 bnj544.3
 |-  D = ( _om \ { (/) } )
4 bnj544.4
 |-  G = ( f u. { <. m , U_ y e. ( f ` p ) _pred ( y , A , R ) >. } )
5 bnj544.5
 |-  ( ta <-> ( f Fn m /\ ph' /\ ps' ) )
6 bnj544.6
 |-  ( si <-> ( m e. D /\ n = suc m /\ p e. m ) )
7 3 bnj923
 |-  ( m e. D -> m e. _om )
8 7 3anim1i
 |-  ( ( m e. D /\ n = suc m /\ p e. m ) -> ( m e. _om /\ n = suc m /\ p e. m ) )
9 6 8 sylbi
 |-  ( si -> ( m e. _om /\ n = suc m /\ p e. m ) )
10 biid
 |-  ( ( m e. _om /\ n = suc m /\ p e. m ) <-> ( m e. _om /\ n = suc m /\ p e. m ) )
11 1 2 4 5 10 bnj543
 |-  ( ( R _FrSe A /\ ta /\ ( m e. _om /\ n = suc m /\ p e. m ) ) -> G Fn n )
12 9 11 syl3an3
 |-  ( ( R _FrSe A /\ ta /\ si ) -> G Fn n )