Metamath Proof Explorer


Theorem bnj958

Description: Technical lemma for bnj69 . 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 bnj958.1
|- C = U_ y e. ( f ` m ) _pred ( y , A , R )
bnj958.2
|- G = ( f u. { <. n , C >. } )
Assertion bnj958
|- ( ( G ` i ) = ( f ` i ) -> A. y ( G ` i ) = ( f ` i ) )

Proof

Step Hyp Ref Expression
1 bnj958.1
 |-  C = U_ y e. ( f ` m ) _pred ( y , A , R )
2 bnj958.2
 |-  G = ( f u. { <. n , C >. } )
3 nfcv
 |-  F/_ y f
4 nfcv
 |-  F/_ y n
5 nfiu1
 |-  F/_ y U_ y e. ( f ` m ) _pred ( y , A , R )
6 1 5 nfcxfr
 |-  F/_ y C
7 4 6 nfop
 |-  F/_ y <. n , C >.
8 7 nfsn
 |-  F/_ y { <. n , C >. }
9 3 8 nfun
 |-  F/_ y ( f u. { <. n , C >. } )
10 2 9 nfcxfr
 |-  F/_ y G
11 nfcv
 |-  F/_ y i
12 10 11 nffv
 |-  F/_ y ( G ` i )
13 12 nfeq1
 |-  F/ y ( G ` i ) = ( f ` i )
14 13 nf5ri
 |-  ( ( G ` i ) = ( f ` i ) -> A. y ( G ` i ) = ( f ` i ) )