Metamath Proof Explorer


Theorem bnj1497

Description: Technical lemma for bnj60 . 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 bnj1497.1
|- B = { d | ( d C_ A /\ A. x e. d _pred ( x , A , R ) C_ d ) }
bnj1497.2
|- Y = <. x , ( f |` _pred ( x , A , R ) ) >.
bnj1497.3
|- C = { f | E. d e. B ( f Fn d /\ A. x e. d ( f ` x ) = ( G ` Y ) ) }
Assertion bnj1497
|- A. g e. C Fun g

Proof

Step Hyp Ref Expression
1 bnj1497.1
 |-  B = { d | ( d C_ A /\ A. x e. d _pred ( x , A , R ) C_ d ) }
2 bnj1497.2
 |-  Y = <. x , ( f |` _pred ( x , A , R ) ) >.
3 bnj1497.3
 |-  C = { f | E. d e. B ( f Fn d /\ A. x e. d ( f ` x ) = ( G ` Y ) ) }
4 3 bnj1317
 |-  ( g e. C -> A. f g e. C )
5 4 nf5i
 |-  F/ f g e. C
6 nfv
 |-  F/ f Fun g
7 5 6 nfim
 |-  F/ f ( g e. C -> Fun g )
8 eleq1w
 |-  ( f = g -> ( f e. C <-> g e. C ) )
9 funeq
 |-  ( f = g -> ( Fun f <-> Fun g ) )
10 8 9 imbi12d
 |-  ( f = g -> ( ( f e. C -> Fun f ) <-> ( g e. C -> Fun g ) ) )
11 3 bnj1436
 |-  ( f e. C -> E. d e. B ( f Fn d /\ A. x e. d ( f ` x ) = ( G ` Y ) ) )
12 11 bnj1299
 |-  ( f e. C -> E. d e. B f Fn d )
13 fnfun
 |-  ( f Fn d -> Fun f )
14 12 13 bnj31
 |-  ( f e. C -> E. d e. B Fun f )
15 14 bnj1265
 |-  ( f e. C -> Fun f )
16 7 10 15 chvarfv
 |-  ( g e. C -> Fun g )
17 16 rgen
 |-  A. g e. C Fun g