Metamath Proof Explorer


Theorem bnj1519

Description: Technical lemma for bnj1500 . 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 bnj1519.1 B = d | d A x d pred x A R d
bnj1519.2 Y = x f pred x A R
bnj1519.3 C = f | d B f Fn d x d f x = G Y
bnj1519.4 F = C
Assertion bnj1519 F x = G x F pred x A R d F x = G x F pred x A R

Proof

Step Hyp Ref Expression
1 bnj1519.1 B = d | d A x d pred x A R d
2 bnj1519.2 Y = x f pred x A R
3 bnj1519.3 C = f | d B f Fn d x d f x = G Y
4 bnj1519.4 F = C
5 nfre1 d d B f Fn d x d f x = G Y
6 5 nfab _ d f | d B f Fn d x d f x = G Y
7 3 6 nfcxfr _ d C
8 7 nfuni _ d C
9 4 8 nfcxfr _ d F
10 nfcv _ d x
11 9 10 nffv _ d F x
12 nfcv _ d G
13 nfcv _ d pred x A R
14 9 13 nfres _ d F pred x A R
15 10 14 nfop _ d x F pred x A R
16 12 15 nffv _ d G x F pred x A R
17 11 16 nfeq d F x = G x F pred x A R
18 17 nf5ri F x = G x F pred x A R d F x = G x F pred x A R